birth order, educational attainment, and earnings - jasmin kantarevic
TRANSCRIPT
Birth Order Educational Attainmentand EarningsAn Investigation Using the PSID
Jasmin KantarevicSteacutephane Mechoulan
a b s t r a c t
We examine the implications of being early in the birth order and whethera pattern exists within large families of falling then rising attainment withrespect to birth order Unlike other studies using US data we go beyondgrade for age and look at racial differences Drawing from OLS and fixedeffects estimations we find that being first-born confers a significant educa-tional advantage that persists when considering earnings being last-bornconfers none These effects are significant for large Black families at thehigh school level and for White families of any size at both high school andcollege levels
I Introduction
Whether birth order affects performance has been an open empiricalquestion for decades In this study we examine whether being early in the birth orderimplies a distinct educational and professional advantage and whether within largefamilies a pattern exists of falling then rising attainment with respect to birth order
The empirical results presented here drawn from the Panel Study of IncomeDynamics (PSID) show that being first-born does confer an advantage while beinglast-born confers none In particular we stress the importance of controlling for theage of the mother at childbirth The age of the mother at childbirth is positively cor-related with a childrsquos education At the same time it is mechanically positively
Jasmin Kantarevic is a senior economist at the Ontario Medical Association and a research affilate at theInstitute for Labor Studies (IZA) Steacutephane Mechoulan is an assistant professor of economics at theUniversity of Toronto The authors thank Gadi Barlevy Chris Jepsen Nancy Qian Imran Rasul seminarparticipants at the University of Toronto and UQAM and two anonymous referees for valuable commentsand suggestions The data used in this article can be obtained beginning March 2007 through February2010 from Jasmin Kantarevic Ontario Medical Association 525 University Ave Suite 300 TorontoOntario M5G 2K7 Canada Jasmin_KantarevicOMAORG[Submitted February 2005 accepted December 2005]ISSN 022-166X E-ISSN 1548-8004 copy 2006 by the Board of Regents of the University of Wisconsin System
THE JOURNAL OF HUMAN RESOURCES XLI 4
correlated with a childrsquos birth order The omitted variable bias results in a clear offsetof the birth-order effect and represents a simple yet unrecognized source of modelmisspecification
A causal interpretation of the previous analysis would be premature Total numberof siblings the age of the mother at childbirth and other covariates such as parentaleducation are likely correlated with unobservable socioeconomic characteristics Inparticular the precise causal determination of early motherhood on childrenrsquos aca-demic outcomes has received considerable attention (for example GeronimusKorenman and Hillemeier 1994 Hofferth and Reid 2002 Lopez-Turley 2003) fol-lowing an even larger debate on the consequences of early pregnancy on mothers them-selves1 Yet even if early motherhood does not cause lower educational attainment fora child it is still possible that first-borns perform relatively better conditional on earlymotherhood
It would be very difficult to find compelling instrumental variables for all ourpotentially endogenous regressors Therefore to provide additional credibility to ourresults we use a fixed effects (FE) model which by construction removes variablesthat are constant within a family As such we take care of unobserved family-levelheterogeneity The results on birth order are broadly consistent with our initial ones
The PSID enables us to check whether those patterns vary by ethnicity and whetherthe effect we find is in the higher educational realm where financing matters In partic-ular we investigate whether birth order influences secondary or postsecondary educationWe find that birth-order effects are relatively stronger for White families Furthermoreboth ordinary least squares (OLS) and FE estimations show that the first-born lead isalready revealed at the high school stage2 Yet the exact mechanism through which first-borns appear to be advantaged is not fully identifiable from our data
Lastly the PSID gives us an opportunity to track outcomes over a longer periodthan just school years Therefore as a final check of the robustness of the results weestimate the impact of birth order on hourly earnings The same patterns emerge sothat when we omit the age of the mother at birth we find no effect whereas when weinclude it we find a strong positive influence of birth order on hourly earnings We donot find compelling evidence of differential birth-order effects on earnings betweenWhite and Black families
Our work relates to an active literature in the economics of the family that is fun-damental to our understanding of the intra-household allocation of resources3 Ourresults are consistent with those found by Black Devereux and Salvanes (2005) inNorway Booth and Kee (2005) in the United Kingdom and Conley and Glauber(2004) in the United States Yet unlike Conley and Glauber (2004) we are able to gobeyond grade for age
The Journal of Human Resources756
1 Obviously the age of the mother at childbirth is linked to a number of variables that should affect a childrsquoseducational attainment Younger mothers are more likely to be single have less human capital etc Alsoadverse effects of unplanned motherhood may dissipate over time (Bronars and Grogger 1993)2 Specifically birth-order effects are significant for large Black families at the high school level only andfor White families of any size these effects are significant at both the high school and college level We alsolook at the probability of repeating a grade conditional on high school completion which does not seem sig-nificantly influenced by birth order3 Birdsall (1979) Behrman (1986) Behrman and Taubman (1986) Kessler (1991) We elaborate on someother studies in the paper
Our contribution is perhaps most closely related to the work of Hanushek (1992)who used a sample of school children from low-income Black families in early 1970sIndiana Hanushekrsquos paper advances that while being early in the birth order impliesa distinct advantage it is entirely due to the higher probability of coming from a smallfamily Following Lindert (1977) the paper also highlights within large families adistinct and sizeable pattern of falling and then rising attainment with respect to birthorder to the point that it becomes best to be last-born In contrast to Hanushek oursample is more representative We are thus able to examine longer-run outcomes andwe also look at racial differences Our empirical results first present a close versionof Hanushekrsquos findings before challenging their robustness by introducing age ofmother at birth in the model and running fixed effects estimations
The rest of the paper is organized as follows Section II presents our data SectionIII shows how birth order affects various educational outcomes through different esti-mation strategies Section IV then extends the analysis to earnings Finally Section Vconcludes
II Description of the Data
Our data come from the Childbirth and Adoption History File(CAHF) a special supplemental file of the PSID The CAHF covers eligible people4
living in a PSID family at the time of the interview in any wave from 1985 through2001
The population examined here (henceforth the ldquoindex personsrdquo) consists of allthose for whom the CAHF sample contains records of the childbirth histories of atleast one of their parents The CAHF allows us to compile information on their birthorder and the total number of children that their parent(s) report(s)
The index persons with missing information on their birth order or for whom thenumber of siblings is not ascertained are necessarily excluded from the sample Toensure that all mothers have completed their fertility so that we correctly identify thetotal number of siblings we further limit the sample to those index persons whosemother was older than 44 in the last year she reported
Siblings are defined based on the childbirth histories of mothers5 In addition tothe birth order and the number of siblings of the index persons we have obtainedadditional demographic information on them and their parents from other PSID filesusing the unique individual identifiers that are present in the PSID main and supple-mental files
Notably the PSID suffers from an important attrition bias More educated peopletend to stick with the questionnaire over longer periods of time thus it appears that
4 Eligible persons are defined as heads or wives of any age and other members of the family unit aged12ndash44 at the time of the interview These individuals are asked retrospective questions about their birth andadoption histories at the time of their first interview In each succeeding wave these histories are updated5 The sample shrinks by 30 percent if siblings are defined based on the childbirth histories of fathers Incase both parents report we were able to identify between siblings and half siblings however this distinc-tion did not change any of our results We include a variable expressing whether both parents report in ourregressions
Kantarevic and Mechoulan 757
Tabl
e 1
Des
crip
tive
Sta
tist
ics
Var
iabl
eSt
anda
rd
Inde
x in
divi
dual
Obs
erva
tions
Mea
nD
evia
tion
Min
imum
Max
imum
Yea
rs o
f co
mpl
eted
edu
catio
n8
147
126
22
131
17Pe
rcen
t com
plet
ed h
igh
scho
ol8
147
082
mdash0
1L
og h
ourl
y ea
rnin
gs in
200
13
028
267
071
minus12
599
Age
(in
200
1)8
318
385
78
7625
89Pe
rcen
t mal
e8
318
05
mdash0
1Pe
rcen
t Whi
te8
318
047
mdash0
1N
umbe
r of
sib
lings
831
84
862
722
16Pe
rcen
t firs
t-bo
rn8
318
027
mdash0
1Pe
rcen
t sec
ond-
born
831
80
27mdash
01
Perc
ent t
hird
-bor
n8
318
017
mdash0
1Pe
rcen
t fou
rth-
born
831
80
11mdash
01
Perc
ent fi
fth-
born
831
80
07mdash
01
Info
rmat
ion
on a
ll si
blin
gs8
318
056
mdash0
1B
oth
pare
nts
repo
rt th
e ch
ildbi
rth
831
80
60mdash
01
Fam
ily in
com
eA
ge 1
ndash62
695
136
399
283
508
976
60A
ge 7
ndash14
457
619
993
173
601
173
255
393
Age
1ndash1
43
474
188
5014
026
109
217
848
0M
othe
r co
ntin
uous
ly m
arri
edA
ge 1
ndash68
318
025
mdash0
1A
ge 7
ndash14
831
80
36mdash
01
Age
1ndash1
48
318
021
mdash0
1M
othe
rA
ge a
t bir
th8
292
261
85
8815
48Y
ears
of
com
plet
ed e
duca
tion
810
211
03
302
120
Fath
erA
ge a
t bir
th5
000
293
26
5417
60Y
ears
of
com
plet
ed e
duca
tion
489
211
13
367
117
Incl
udes
ind
ex p
erso
ns w
ho h
ave
at l
east
one
sib
ling
who
are
25
year
s or
old
er i
n 20
01 a
nd w
hose
mot
her
is a
t le
ast
44 y
ears
old
in
the
last
yea
r sh
e re
port
ed T
he n
umbe
r of
dis
tinct
fam
ilies
is
311
2
The Journal of Human Resources758
Kantarevic and Mechoulan 759
education is decreasing over cohorts which is of course untrue according to the USCensus Because a first-born is older than other siblings by definition this alonecould in theory produce a spurious positive impact of being first-born on educationWe have checked that this problem is of no consequence for our results6
The summary statistics of our sample are presented in Table 1 The detaileddescription of variables is relegated to Appendix 1 We found more than 8000 indexpersons (from more than 3100 distinct families) older than 24 in 2001 with at leastone other sibling and whose mother has completed her fertility This is to be con-trasted with Conley and Glauber (2004) who use larger sample from the US Censusbut focus only on children under the age of 20 living at home
The main dependent variablemdashyears of completed educationmdashhas an average of1262 years7 About 82 percent of those selected index persons have at least 12 years ofeducation that is to say have completed high school8 Our measure of earningsmdashloghourly wage in 2001mdashshows an average corresponding to $145hour However theinformation on hourly wages or salary income is not available for most index persons
The average age in our sample is 39 About half of respondents are male and 47percent are White The average number of siblings is 486 This high number is con-sistent with the PSID oversampling minorities and low-income populations Fifty-sixpercent of the index persons have all their siblings reporting and 60 percent have boththeir parents reporting their childbirth history
We improved our analysis by including important observed family level-effects thatvary across parity family income and whether the mother is married Wheneveravailable we constructed the corresponding information for each of the first 14 yearsof life of each index person9 The main limitation is that information on familyincome cannot be recovered for many index individuals
Lastly we include two variables describing characteristics of index individualsrsquo par-ents namely education (11 years for both mother and father on average) and the age ofthe parents at birth of index persons (26 for mothers and 29 for fathers on average)
III Methods and Results
A The First-Born Effect
We first use an OLS estimation with robust standard errors clustered by family unit(identified by the mother) which relaxes the independence assumption between the
6 The regressions presented in this article contain age controls that separate cohort from birth order effects 7 A more appropriate variable would be education at age 25 However the number of observations avail-able would drop considerably and we would not be able to run estimations by sibling size All of our otherresults when running estimations that control for siblings size hold when replacing education with educationat age 25 for those where such information can be traced8 A negligible fraction of those who declare a certain education level at some point in their life declare lesseducation later Removing such observations did not alter our results We therefore choose the latest educa-tion level reported as our variable of interest9 We then ran our regressions using the average of these variables for three age groups 1ndash6 7ndash14 and1ndash14 For each age group the averages are respectively calculated only if the information is present in atleast half of the years of the age group
The Journal of Human Resources760
error terms and requires only that the observations be independent across clusters10
In Table 2 we first test the hypothesis that being early in the birth order implies a dis-tinct advantage that is entirely due to the higher probability of coming from a smallfamily
Columns 1 and 2 of Table 2 reject that claim but help us understand why it mayhave been made In Column 1 we omit the number of siblings therefore the signif-icant coefficient on first-born reflects not only the birth order effect but also the prob-ability of coming from a small family In Column 2 the inclusion of the number ofsiblings leaves the coefficient on first-born insignificant
In Column 3 we include age of the mother at childbirth and find a positive andhighly significant effect of being first-born on years of education This effect is con-firmed when including the fatherrsquos characteristics in Column 4 where both a father anda mother report Often not all siblings report this is especially the case for large fam-ilies To check if we are biasing our results by including such families in Column 5 werestrict our attention to families with complete information on all siblings The findingsare similar there too further showing that they could not be driven by selective attri-tion within families by birth order In all specifications we find a stronger effect amongWhite families
The results presented here are for the impact of being first-born in families of morethan one child This particular procedure takes advantage of the full size of our sam-ple and can be useful when there are not enough observations to run separate estima-tions for different siblingsrsquo sizes11 We see that it allows us to reveal a significant androbust birth order effect
However we still obtain similar results when looking at individual birth ordereffects by siblingsrsquo size in Table 3 where all specifications include age of the motherat childbirth Although large families show higher birth order point estimates theeffect is present in two-sibling families as well Note that the coefficient on first-bornis only weakly significant in Column 4mdashfamilies of five siblingsmdashlikely because ofthe small sample size
The reason why the inclusion of the age of the mother at childbirth makes the coef-ficient on first-born larger in magnitude and more significant is clear The age of themother at childbirth is mechanically positively correlated with birth order and evenmore strongly across large families Conversely we see that it is positively correlatedwith a childrsquos education Then if having a high birth order carries a negative impacton education the two effects of birth order and age of the mother at childbirth com-pete against one another Therefore the coefficient on first-born in Table 2 Column 2reflects an omitted variable bias The results hold for both males and females formothers with or without more than a high school education We also found that spac-ing between births be it that of the first-born child with respect to the second-born orto the last-born child does not alter the conclusions either Additional OLS regres-sions confirmed that the effect is significantly present among White families of any
10 We also used random effects procedures but because they yield almost identical results as those withthe family clustered standard errors those are not reported11 For example we found a significant birth-order effect when considering separately mothers who firstgave birth early and mothers who first gave birth ldquolaterdquo (using various definitions of ldquoearlyrdquo and ldquolaterdquo) yetwe do not have enough observations to split the sample by maternal age and individual siblings size
Kantarevic and Mechoulan 761Ta
ble
2O
LS
Reg
ress
ion
wit
h D
epen
dent
Var
iabl
e E
duca
tion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
016
20
012
028
80
239
026
8(0
068
)
(00
69)
(00
72)
(0
098
)
(00
84)
To
tal n
umbe
r of
sib
lings
minus01
04minus0
121
minus01
08minus0
125
(00
15)
(0
015
)
(00
19)
(0
029
)
Age
of
mot
her
at c
hild
birt
h0
058
006
10
065
(00
05)
(0
011
)
(00
08)
d[
Mal
e]minus0
205
minus02
1minus0
226
minus01
86minus0
159
(00
47)
(0
046
)
(00
46)
(0
058
)
(00
57)
A
ge0
121
015
90
162
014
30
087
(00
27)
(0
027
)
(00
27)
(0
039
)
(00
40)
A
ge2
minus00
01minus0
001
minus00
01minus0
001
minus00
03(0
000
3)
(0
000
3)
(0
000
3)
(0
001
)
(00
001)
d[W
hite
]0
119
minus00
03minus0
099
minus02
95minus0
107
(00
72)
(00
73)
(00
71)
(00
87)
(0
098
)d[
first
-bor
n] times
d[W
hite
]0
126
019
30
184
028
60
172
(00
92)
(00
92)
(0
092
)
(01
15)
(0
104
)M
othe
rrsquos
educ
atio
n0
213
019
80
199
011
40
236
(00
12)
(0
012
)
(00
12)
(0
017
)
(00
18)
d[
all s
iblin
gs r
epor
t]0
261
009
60
181
014
4(0
068
)
(00
69)
(00
69)
(0
089
)d[
both
par
ents
rep
ort]
052
30
553
052
00
533
(00
63)
(0
062
)
(00
61)
(0
081
)
Fath
errsquos
edu
catio
n0
125
(00
12)
A
ge o
f fa
ther
at c
hild
birt
h0
006
(00
09)
Con
stan
t6
713
671
75
073
516
25
848
(05
28)
(05
31)
(0
541
)
(07
75)
(0
776
)
R2
015
780
1691
018
890
2009
019
82N
umbe
r of
obs
erva
tions
792
87
928
792
87
766
454
1N
umbe
r of
fam
ily c
lust
ers
311
23
112
311
21
869
173
2
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
correlated with a childrsquos birth order The omitted variable bias results in a clear offsetof the birth-order effect and represents a simple yet unrecognized source of modelmisspecification
A causal interpretation of the previous analysis would be premature Total numberof siblings the age of the mother at childbirth and other covariates such as parentaleducation are likely correlated with unobservable socioeconomic characteristics Inparticular the precise causal determination of early motherhood on childrenrsquos aca-demic outcomes has received considerable attention (for example GeronimusKorenman and Hillemeier 1994 Hofferth and Reid 2002 Lopez-Turley 2003) fol-lowing an even larger debate on the consequences of early pregnancy on mothers them-selves1 Yet even if early motherhood does not cause lower educational attainment fora child it is still possible that first-borns perform relatively better conditional on earlymotherhood
It would be very difficult to find compelling instrumental variables for all ourpotentially endogenous regressors Therefore to provide additional credibility to ourresults we use a fixed effects (FE) model which by construction removes variablesthat are constant within a family As such we take care of unobserved family-levelheterogeneity The results on birth order are broadly consistent with our initial ones
The PSID enables us to check whether those patterns vary by ethnicity and whetherthe effect we find is in the higher educational realm where financing matters In partic-ular we investigate whether birth order influences secondary or postsecondary educationWe find that birth-order effects are relatively stronger for White families Furthermoreboth ordinary least squares (OLS) and FE estimations show that the first-born lead isalready revealed at the high school stage2 Yet the exact mechanism through which first-borns appear to be advantaged is not fully identifiable from our data
Lastly the PSID gives us an opportunity to track outcomes over a longer periodthan just school years Therefore as a final check of the robustness of the results weestimate the impact of birth order on hourly earnings The same patterns emerge sothat when we omit the age of the mother at birth we find no effect whereas when weinclude it we find a strong positive influence of birth order on hourly earnings We donot find compelling evidence of differential birth-order effects on earnings betweenWhite and Black families
Our work relates to an active literature in the economics of the family that is fun-damental to our understanding of the intra-household allocation of resources3 Ourresults are consistent with those found by Black Devereux and Salvanes (2005) inNorway Booth and Kee (2005) in the United Kingdom and Conley and Glauber(2004) in the United States Yet unlike Conley and Glauber (2004) we are able to gobeyond grade for age
The Journal of Human Resources756
1 Obviously the age of the mother at childbirth is linked to a number of variables that should affect a childrsquoseducational attainment Younger mothers are more likely to be single have less human capital etc Alsoadverse effects of unplanned motherhood may dissipate over time (Bronars and Grogger 1993)2 Specifically birth-order effects are significant for large Black families at the high school level only andfor White families of any size these effects are significant at both the high school and college level We alsolook at the probability of repeating a grade conditional on high school completion which does not seem sig-nificantly influenced by birth order3 Birdsall (1979) Behrman (1986) Behrman and Taubman (1986) Kessler (1991) We elaborate on someother studies in the paper
Our contribution is perhaps most closely related to the work of Hanushek (1992)who used a sample of school children from low-income Black families in early 1970sIndiana Hanushekrsquos paper advances that while being early in the birth order impliesa distinct advantage it is entirely due to the higher probability of coming from a smallfamily Following Lindert (1977) the paper also highlights within large families adistinct and sizeable pattern of falling and then rising attainment with respect to birthorder to the point that it becomes best to be last-born In contrast to Hanushek oursample is more representative We are thus able to examine longer-run outcomes andwe also look at racial differences Our empirical results first present a close versionof Hanushekrsquos findings before challenging their robustness by introducing age ofmother at birth in the model and running fixed effects estimations
The rest of the paper is organized as follows Section II presents our data SectionIII shows how birth order affects various educational outcomes through different esti-mation strategies Section IV then extends the analysis to earnings Finally Section Vconcludes
II Description of the Data
Our data come from the Childbirth and Adoption History File(CAHF) a special supplemental file of the PSID The CAHF covers eligible people4
living in a PSID family at the time of the interview in any wave from 1985 through2001
The population examined here (henceforth the ldquoindex personsrdquo) consists of allthose for whom the CAHF sample contains records of the childbirth histories of atleast one of their parents The CAHF allows us to compile information on their birthorder and the total number of children that their parent(s) report(s)
The index persons with missing information on their birth order or for whom thenumber of siblings is not ascertained are necessarily excluded from the sample Toensure that all mothers have completed their fertility so that we correctly identify thetotal number of siblings we further limit the sample to those index persons whosemother was older than 44 in the last year she reported
Siblings are defined based on the childbirth histories of mothers5 In addition tothe birth order and the number of siblings of the index persons we have obtainedadditional demographic information on them and their parents from other PSID filesusing the unique individual identifiers that are present in the PSID main and supple-mental files
Notably the PSID suffers from an important attrition bias More educated peopletend to stick with the questionnaire over longer periods of time thus it appears that
4 Eligible persons are defined as heads or wives of any age and other members of the family unit aged12ndash44 at the time of the interview These individuals are asked retrospective questions about their birth andadoption histories at the time of their first interview In each succeeding wave these histories are updated5 The sample shrinks by 30 percent if siblings are defined based on the childbirth histories of fathers Incase both parents report we were able to identify between siblings and half siblings however this distinc-tion did not change any of our results We include a variable expressing whether both parents report in ourregressions
Kantarevic and Mechoulan 757
Tabl
e 1
Des
crip
tive
Sta
tist
ics
Var
iabl
eSt
anda
rd
Inde
x in
divi
dual
Obs
erva
tions
Mea
nD
evia
tion
Min
imum
Max
imum
Yea
rs o
f co
mpl
eted
edu
catio
n8
147
126
22
131
17Pe
rcen
t com
plet
ed h
igh
scho
ol8
147
082
mdash0
1L
og h
ourl
y ea
rnin
gs in
200
13
028
267
071
minus12
599
Age
(in
200
1)8
318
385
78
7625
89Pe
rcen
t mal
e8
318
05
mdash0
1Pe
rcen
t Whi
te8
318
047
mdash0
1N
umbe
r of
sib
lings
831
84
862
722
16Pe
rcen
t firs
t-bo
rn8
318
027
mdash0
1Pe
rcen
t sec
ond-
born
831
80
27mdash
01
Perc
ent t
hird
-bor
n8
318
017
mdash0
1Pe
rcen
t fou
rth-
born
831
80
11mdash
01
Perc
ent fi
fth-
born
831
80
07mdash
01
Info
rmat
ion
on a
ll si
blin
gs8
318
056
mdash0
1B
oth
pare
nts
repo
rt th
e ch
ildbi
rth
831
80
60mdash
01
Fam
ily in
com
eA
ge 1
ndash62
695
136
399
283
508
976
60A
ge 7
ndash14
457
619
993
173
601
173
255
393
Age
1ndash1
43
474
188
5014
026
109
217
848
0M
othe
r co
ntin
uous
ly m
arri
edA
ge 1
ndash68
318
025
mdash0
1A
ge 7
ndash14
831
80
36mdash
01
Age
1ndash1
48
318
021
mdash0
1M
othe
rA
ge a
t bir
th8
292
261
85
8815
48Y
ears
of
com
plet
ed e
duca
tion
810
211
03
302
120
Fath
erA
ge a
t bir
th5
000
293
26
5417
60Y
ears
of
com
plet
ed e
duca
tion
489
211
13
367
117
Incl
udes
ind
ex p
erso
ns w
ho h
ave
at l
east
one
sib
ling
who
are
25
year
s or
old
er i
n 20
01 a
nd w
hose
mot
her
is a
t le
ast
44 y
ears
old
in
the
last
yea
r sh
e re
port
ed T
he n
umbe
r of
dis
tinct
fam
ilies
is
311
2
The Journal of Human Resources758
Kantarevic and Mechoulan 759
education is decreasing over cohorts which is of course untrue according to the USCensus Because a first-born is older than other siblings by definition this alonecould in theory produce a spurious positive impact of being first-born on educationWe have checked that this problem is of no consequence for our results6
The summary statistics of our sample are presented in Table 1 The detaileddescription of variables is relegated to Appendix 1 We found more than 8000 indexpersons (from more than 3100 distinct families) older than 24 in 2001 with at leastone other sibling and whose mother has completed her fertility This is to be con-trasted with Conley and Glauber (2004) who use larger sample from the US Censusbut focus only on children under the age of 20 living at home
The main dependent variablemdashyears of completed educationmdashhas an average of1262 years7 About 82 percent of those selected index persons have at least 12 years ofeducation that is to say have completed high school8 Our measure of earningsmdashloghourly wage in 2001mdashshows an average corresponding to $145hour However theinformation on hourly wages or salary income is not available for most index persons
The average age in our sample is 39 About half of respondents are male and 47percent are White The average number of siblings is 486 This high number is con-sistent with the PSID oversampling minorities and low-income populations Fifty-sixpercent of the index persons have all their siblings reporting and 60 percent have boththeir parents reporting their childbirth history
We improved our analysis by including important observed family level-effects thatvary across parity family income and whether the mother is married Wheneveravailable we constructed the corresponding information for each of the first 14 yearsof life of each index person9 The main limitation is that information on familyincome cannot be recovered for many index individuals
Lastly we include two variables describing characteristics of index individualsrsquo par-ents namely education (11 years for both mother and father on average) and the age ofthe parents at birth of index persons (26 for mothers and 29 for fathers on average)
III Methods and Results
A The First-Born Effect
We first use an OLS estimation with robust standard errors clustered by family unit(identified by the mother) which relaxes the independence assumption between the
6 The regressions presented in this article contain age controls that separate cohort from birth order effects 7 A more appropriate variable would be education at age 25 However the number of observations avail-able would drop considerably and we would not be able to run estimations by sibling size All of our otherresults when running estimations that control for siblings size hold when replacing education with educationat age 25 for those where such information can be traced8 A negligible fraction of those who declare a certain education level at some point in their life declare lesseducation later Removing such observations did not alter our results We therefore choose the latest educa-tion level reported as our variable of interest9 We then ran our regressions using the average of these variables for three age groups 1ndash6 7ndash14 and1ndash14 For each age group the averages are respectively calculated only if the information is present in atleast half of the years of the age group
The Journal of Human Resources760
error terms and requires only that the observations be independent across clusters10
In Table 2 we first test the hypothesis that being early in the birth order implies a dis-tinct advantage that is entirely due to the higher probability of coming from a smallfamily
Columns 1 and 2 of Table 2 reject that claim but help us understand why it mayhave been made In Column 1 we omit the number of siblings therefore the signif-icant coefficient on first-born reflects not only the birth order effect but also the prob-ability of coming from a small family In Column 2 the inclusion of the number ofsiblings leaves the coefficient on first-born insignificant
In Column 3 we include age of the mother at childbirth and find a positive andhighly significant effect of being first-born on years of education This effect is con-firmed when including the fatherrsquos characteristics in Column 4 where both a father anda mother report Often not all siblings report this is especially the case for large fam-ilies To check if we are biasing our results by including such families in Column 5 werestrict our attention to families with complete information on all siblings The findingsare similar there too further showing that they could not be driven by selective attri-tion within families by birth order In all specifications we find a stronger effect amongWhite families
The results presented here are for the impact of being first-born in families of morethan one child This particular procedure takes advantage of the full size of our sam-ple and can be useful when there are not enough observations to run separate estima-tions for different siblingsrsquo sizes11 We see that it allows us to reveal a significant androbust birth order effect
However we still obtain similar results when looking at individual birth ordereffects by siblingsrsquo size in Table 3 where all specifications include age of the motherat childbirth Although large families show higher birth order point estimates theeffect is present in two-sibling families as well Note that the coefficient on first-bornis only weakly significant in Column 4mdashfamilies of five siblingsmdashlikely because ofthe small sample size
The reason why the inclusion of the age of the mother at childbirth makes the coef-ficient on first-born larger in magnitude and more significant is clear The age of themother at childbirth is mechanically positively correlated with birth order and evenmore strongly across large families Conversely we see that it is positively correlatedwith a childrsquos education Then if having a high birth order carries a negative impacton education the two effects of birth order and age of the mother at childbirth com-pete against one another Therefore the coefficient on first-born in Table 2 Column 2reflects an omitted variable bias The results hold for both males and females formothers with or without more than a high school education We also found that spac-ing between births be it that of the first-born child with respect to the second-born orto the last-born child does not alter the conclusions either Additional OLS regres-sions confirmed that the effect is significantly present among White families of any
10 We also used random effects procedures but because they yield almost identical results as those withthe family clustered standard errors those are not reported11 For example we found a significant birth-order effect when considering separately mothers who firstgave birth early and mothers who first gave birth ldquolaterdquo (using various definitions of ldquoearlyrdquo and ldquolaterdquo) yetwe do not have enough observations to split the sample by maternal age and individual siblings size
Kantarevic and Mechoulan 761Ta
ble
2O
LS
Reg
ress
ion
wit
h D
epen
dent
Var
iabl
e E
duca
tion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
016
20
012
028
80
239
026
8(0
068
)
(00
69)
(00
72)
(0
098
)
(00
84)
To
tal n
umbe
r of
sib
lings
minus01
04minus0
121
minus01
08minus0
125
(00
15)
(0
015
)
(00
19)
(0
029
)
Age
of
mot
her
at c
hild
birt
h0
058
006
10
065
(00
05)
(0
011
)
(00
08)
d[
Mal
e]minus0
205
minus02
1minus0
226
minus01
86minus0
159
(00
47)
(0
046
)
(00
46)
(0
058
)
(00
57)
A
ge0
121
015
90
162
014
30
087
(00
27)
(0
027
)
(00
27)
(0
039
)
(00
40)
A
ge2
minus00
01minus0
001
minus00
01minus0
001
minus00
03(0
000
3)
(0
000
3)
(0
000
3)
(0
001
)
(00
001)
d[W
hite
]0
119
minus00
03minus0
099
minus02
95minus0
107
(00
72)
(00
73)
(00
71)
(00
87)
(0
098
)d[
first
-bor
n] times
d[W
hite
]0
126
019
30
184
028
60
172
(00
92)
(00
92)
(0
092
)
(01
15)
(0
104
)M
othe
rrsquos
educ
atio
n0
213
019
80
199
011
40
236
(00
12)
(0
012
)
(00
12)
(0
017
)
(00
18)
d[
all s
iblin
gs r
epor
t]0
261
009
60
181
014
4(0
068
)
(00
69)
(00
69)
(0
089
)d[
both
par
ents
rep
ort]
052
30
553
052
00
533
(00
63)
(0
062
)
(00
61)
(0
081
)
Fath
errsquos
edu
catio
n0
125
(00
12)
A
ge o
f fa
ther
at c
hild
birt
h0
006
(00
09)
Con
stan
t6
713
671
75
073
516
25
848
(05
28)
(05
31)
(0
541
)
(07
75)
(0
776
)
R2
015
780
1691
018
890
2009
019
82N
umbe
r of
obs
erva
tions
792
87
928
792
87
766
454
1N
umbe
r of
fam
ily c
lust
ers
311
23
112
311
21
869
173
2
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Our contribution is perhaps most closely related to the work of Hanushek (1992)who used a sample of school children from low-income Black families in early 1970sIndiana Hanushekrsquos paper advances that while being early in the birth order impliesa distinct advantage it is entirely due to the higher probability of coming from a smallfamily Following Lindert (1977) the paper also highlights within large families adistinct and sizeable pattern of falling and then rising attainment with respect to birthorder to the point that it becomes best to be last-born In contrast to Hanushek oursample is more representative We are thus able to examine longer-run outcomes andwe also look at racial differences Our empirical results first present a close versionof Hanushekrsquos findings before challenging their robustness by introducing age ofmother at birth in the model and running fixed effects estimations
The rest of the paper is organized as follows Section II presents our data SectionIII shows how birth order affects various educational outcomes through different esti-mation strategies Section IV then extends the analysis to earnings Finally Section Vconcludes
II Description of the Data
Our data come from the Childbirth and Adoption History File(CAHF) a special supplemental file of the PSID The CAHF covers eligible people4
living in a PSID family at the time of the interview in any wave from 1985 through2001
The population examined here (henceforth the ldquoindex personsrdquo) consists of allthose for whom the CAHF sample contains records of the childbirth histories of atleast one of their parents The CAHF allows us to compile information on their birthorder and the total number of children that their parent(s) report(s)
The index persons with missing information on their birth order or for whom thenumber of siblings is not ascertained are necessarily excluded from the sample Toensure that all mothers have completed their fertility so that we correctly identify thetotal number of siblings we further limit the sample to those index persons whosemother was older than 44 in the last year she reported
Siblings are defined based on the childbirth histories of mothers5 In addition tothe birth order and the number of siblings of the index persons we have obtainedadditional demographic information on them and their parents from other PSID filesusing the unique individual identifiers that are present in the PSID main and supple-mental files
Notably the PSID suffers from an important attrition bias More educated peopletend to stick with the questionnaire over longer periods of time thus it appears that
4 Eligible persons are defined as heads or wives of any age and other members of the family unit aged12ndash44 at the time of the interview These individuals are asked retrospective questions about their birth andadoption histories at the time of their first interview In each succeeding wave these histories are updated5 The sample shrinks by 30 percent if siblings are defined based on the childbirth histories of fathers Incase both parents report we were able to identify between siblings and half siblings however this distinc-tion did not change any of our results We include a variable expressing whether both parents report in ourregressions
Kantarevic and Mechoulan 757
Tabl
e 1
Des
crip
tive
Sta
tist
ics
Var
iabl
eSt
anda
rd
Inde
x in
divi
dual
Obs
erva
tions
Mea
nD
evia
tion
Min
imum
Max
imum
Yea
rs o
f co
mpl
eted
edu
catio
n8
147
126
22
131
17Pe
rcen
t com
plet
ed h
igh
scho
ol8
147
082
mdash0
1L
og h
ourl
y ea
rnin
gs in
200
13
028
267
071
minus12
599
Age
(in
200
1)8
318
385
78
7625
89Pe
rcen
t mal
e8
318
05
mdash0
1Pe
rcen
t Whi
te8
318
047
mdash0
1N
umbe
r of
sib
lings
831
84
862
722
16Pe
rcen
t firs
t-bo
rn8
318
027
mdash0
1Pe
rcen
t sec
ond-
born
831
80
27mdash
01
Perc
ent t
hird
-bor
n8
318
017
mdash0
1Pe
rcen
t fou
rth-
born
831
80
11mdash
01
Perc
ent fi
fth-
born
831
80
07mdash
01
Info
rmat
ion
on a
ll si
blin
gs8
318
056
mdash0
1B
oth
pare
nts
repo
rt th
e ch
ildbi
rth
831
80
60mdash
01
Fam
ily in
com
eA
ge 1
ndash62
695
136
399
283
508
976
60A
ge 7
ndash14
457
619
993
173
601
173
255
393
Age
1ndash1
43
474
188
5014
026
109
217
848
0M
othe
r co
ntin
uous
ly m
arri
edA
ge 1
ndash68
318
025
mdash0
1A
ge 7
ndash14
831
80
36mdash
01
Age
1ndash1
48
318
021
mdash0
1M
othe
rA
ge a
t bir
th8
292
261
85
8815
48Y
ears
of
com
plet
ed e
duca
tion
810
211
03
302
120
Fath
erA
ge a
t bir
th5
000
293
26
5417
60Y
ears
of
com
plet
ed e
duca
tion
489
211
13
367
117
Incl
udes
ind
ex p
erso
ns w
ho h
ave
at l
east
one
sib
ling
who
are
25
year
s or
old
er i
n 20
01 a
nd w
hose
mot
her
is a
t le
ast
44 y
ears
old
in
the
last
yea
r sh
e re
port
ed T
he n
umbe
r of
dis
tinct
fam
ilies
is
311
2
The Journal of Human Resources758
Kantarevic and Mechoulan 759
education is decreasing over cohorts which is of course untrue according to the USCensus Because a first-born is older than other siblings by definition this alonecould in theory produce a spurious positive impact of being first-born on educationWe have checked that this problem is of no consequence for our results6
The summary statistics of our sample are presented in Table 1 The detaileddescription of variables is relegated to Appendix 1 We found more than 8000 indexpersons (from more than 3100 distinct families) older than 24 in 2001 with at leastone other sibling and whose mother has completed her fertility This is to be con-trasted with Conley and Glauber (2004) who use larger sample from the US Censusbut focus only on children under the age of 20 living at home
The main dependent variablemdashyears of completed educationmdashhas an average of1262 years7 About 82 percent of those selected index persons have at least 12 years ofeducation that is to say have completed high school8 Our measure of earningsmdashloghourly wage in 2001mdashshows an average corresponding to $145hour However theinformation on hourly wages or salary income is not available for most index persons
The average age in our sample is 39 About half of respondents are male and 47percent are White The average number of siblings is 486 This high number is con-sistent with the PSID oversampling minorities and low-income populations Fifty-sixpercent of the index persons have all their siblings reporting and 60 percent have boththeir parents reporting their childbirth history
We improved our analysis by including important observed family level-effects thatvary across parity family income and whether the mother is married Wheneveravailable we constructed the corresponding information for each of the first 14 yearsof life of each index person9 The main limitation is that information on familyincome cannot be recovered for many index individuals
Lastly we include two variables describing characteristics of index individualsrsquo par-ents namely education (11 years for both mother and father on average) and the age ofthe parents at birth of index persons (26 for mothers and 29 for fathers on average)
III Methods and Results
A The First-Born Effect
We first use an OLS estimation with robust standard errors clustered by family unit(identified by the mother) which relaxes the independence assumption between the
6 The regressions presented in this article contain age controls that separate cohort from birth order effects 7 A more appropriate variable would be education at age 25 However the number of observations avail-able would drop considerably and we would not be able to run estimations by sibling size All of our otherresults when running estimations that control for siblings size hold when replacing education with educationat age 25 for those where such information can be traced8 A negligible fraction of those who declare a certain education level at some point in their life declare lesseducation later Removing such observations did not alter our results We therefore choose the latest educa-tion level reported as our variable of interest9 We then ran our regressions using the average of these variables for three age groups 1ndash6 7ndash14 and1ndash14 For each age group the averages are respectively calculated only if the information is present in atleast half of the years of the age group
The Journal of Human Resources760
error terms and requires only that the observations be independent across clusters10
In Table 2 we first test the hypothesis that being early in the birth order implies a dis-tinct advantage that is entirely due to the higher probability of coming from a smallfamily
Columns 1 and 2 of Table 2 reject that claim but help us understand why it mayhave been made In Column 1 we omit the number of siblings therefore the signif-icant coefficient on first-born reflects not only the birth order effect but also the prob-ability of coming from a small family In Column 2 the inclusion of the number ofsiblings leaves the coefficient on first-born insignificant
In Column 3 we include age of the mother at childbirth and find a positive andhighly significant effect of being first-born on years of education This effect is con-firmed when including the fatherrsquos characteristics in Column 4 where both a father anda mother report Often not all siblings report this is especially the case for large fam-ilies To check if we are biasing our results by including such families in Column 5 werestrict our attention to families with complete information on all siblings The findingsare similar there too further showing that they could not be driven by selective attri-tion within families by birth order In all specifications we find a stronger effect amongWhite families
The results presented here are for the impact of being first-born in families of morethan one child This particular procedure takes advantage of the full size of our sam-ple and can be useful when there are not enough observations to run separate estima-tions for different siblingsrsquo sizes11 We see that it allows us to reveal a significant androbust birth order effect
However we still obtain similar results when looking at individual birth ordereffects by siblingsrsquo size in Table 3 where all specifications include age of the motherat childbirth Although large families show higher birth order point estimates theeffect is present in two-sibling families as well Note that the coefficient on first-bornis only weakly significant in Column 4mdashfamilies of five siblingsmdashlikely because ofthe small sample size
The reason why the inclusion of the age of the mother at childbirth makes the coef-ficient on first-born larger in magnitude and more significant is clear The age of themother at childbirth is mechanically positively correlated with birth order and evenmore strongly across large families Conversely we see that it is positively correlatedwith a childrsquos education Then if having a high birth order carries a negative impacton education the two effects of birth order and age of the mother at childbirth com-pete against one another Therefore the coefficient on first-born in Table 2 Column 2reflects an omitted variable bias The results hold for both males and females formothers with or without more than a high school education We also found that spac-ing between births be it that of the first-born child with respect to the second-born orto the last-born child does not alter the conclusions either Additional OLS regres-sions confirmed that the effect is significantly present among White families of any
10 We also used random effects procedures but because they yield almost identical results as those withthe family clustered standard errors those are not reported11 For example we found a significant birth-order effect when considering separately mothers who firstgave birth early and mothers who first gave birth ldquolaterdquo (using various definitions of ldquoearlyrdquo and ldquolaterdquo) yetwe do not have enough observations to split the sample by maternal age and individual siblings size
Kantarevic and Mechoulan 761Ta
ble
2O
LS
Reg
ress
ion
wit
h D
epen
dent
Var
iabl
e E
duca
tion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
016
20
012
028
80
239
026
8(0
068
)
(00
69)
(00
72)
(0
098
)
(00
84)
To
tal n
umbe
r of
sib
lings
minus01
04minus0
121
minus01
08minus0
125
(00
15)
(0
015
)
(00
19)
(0
029
)
Age
of
mot
her
at c
hild
birt
h0
058
006
10
065
(00
05)
(0
011
)
(00
08)
d[
Mal
e]minus0
205
minus02
1minus0
226
minus01
86minus0
159
(00
47)
(0
046
)
(00
46)
(0
058
)
(00
57)
A
ge0
121
015
90
162
014
30
087
(00
27)
(0
027
)
(00
27)
(0
039
)
(00
40)
A
ge2
minus00
01minus0
001
minus00
01minus0
001
minus00
03(0
000
3)
(0
000
3)
(0
000
3)
(0
001
)
(00
001)
d[W
hite
]0
119
minus00
03minus0
099
minus02
95minus0
107
(00
72)
(00
73)
(00
71)
(00
87)
(0
098
)d[
first
-bor
n] times
d[W
hite
]0
126
019
30
184
028
60
172
(00
92)
(00
92)
(0
092
)
(01
15)
(0
104
)M
othe
rrsquos
educ
atio
n0
213
019
80
199
011
40
236
(00
12)
(0
012
)
(00
12)
(0
017
)
(00
18)
d[
all s
iblin
gs r
epor
t]0
261
009
60
181
014
4(0
068
)
(00
69)
(00
69)
(0
089
)d[
both
par
ents
rep
ort]
052
30
553
052
00
533
(00
63)
(0
062
)
(00
61)
(0
081
)
Fath
errsquos
edu
catio
n0
125
(00
12)
A
ge o
f fa
ther
at c
hild
birt
h0
006
(00
09)
Con
stan
t6
713
671
75
073
516
25
848
(05
28)
(05
31)
(0
541
)
(07
75)
(0
776
)
R2
015
780
1691
018
890
2009
019
82N
umbe
r of
obs
erva
tions
792
87
928
792
87
766
454
1N
umbe
r of
fam
ily c
lust
ers
311
23
112
311
21
869
173
2
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Tabl
e 1
Des
crip
tive
Sta
tist
ics
Var
iabl
eSt
anda
rd
Inde
x in
divi
dual
Obs
erva
tions
Mea
nD
evia
tion
Min
imum
Max
imum
Yea
rs o
f co
mpl
eted
edu
catio
n8
147
126
22
131
17Pe
rcen
t com
plet
ed h
igh
scho
ol8
147
082
mdash0
1L
og h
ourl
y ea
rnin
gs in
200
13
028
267
071
minus12
599
Age
(in
200
1)8
318
385
78
7625
89Pe
rcen
t mal
e8
318
05
mdash0
1Pe
rcen
t Whi
te8
318
047
mdash0
1N
umbe
r of
sib
lings
831
84
862
722
16Pe
rcen
t firs
t-bo
rn8
318
027
mdash0
1Pe
rcen
t sec
ond-
born
831
80
27mdash
01
Perc
ent t
hird
-bor
n8
318
017
mdash0
1Pe
rcen
t fou
rth-
born
831
80
11mdash
01
Perc
ent fi
fth-
born
831
80
07mdash
01
Info
rmat
ion
on a
ll si
blin
gs8
318
056
mdash0
1B
oth
pare
nts
repo
rt th
e ch
ildbi
rth
831
80
60mdash
01
Fam
ily in
com
eA
ge 1
ndash62
695
136
399
283
508
976
60A
ge 7
ndash14
457
619
993
173
601
173
255
393
Age
1ndash1
43
474
188
5014
026
109
217
848
0M
othe
r co
ntin
uous
ly m
arri
edA
ge 1
ndash68
318
025
mdash0
1A
ge 7
ndash14
831
80
36mdash
01
Age
1ndash1
48
318
021
mdash0
1M
othe
rA
ge a
t bir
th8
292
261
85
8815
48Y
ears
of
com
plet
ed e
duca
tion
810
211
03
302
120
Fath
erA
ge a
t bir
th5
000
293
26
5417
60Y
ears
of
com
plet
ed e
duca
tion
489
211
13
367
117
Incl
udes
ind
ex p
erso
ns w
ho h
ave
at l
east
one
sib
ling
who
are
25
year
s or
old
er i
n 20
01 a
nd w
hose
mot
her
is a
t le
ast
44 y
ears
old
in
the
last
yea
r sh
e re
port
ed T
he n
umbe
r of
dis
tinct
fam
ilies
is
311
2
The Journal of Human Resources758
Kantarevic and Mechoulan 759
education is decreasing over cohorts which is of course untrue according to the USCensus Because a first-born is older than other siblings by definition this alonecould in theory produce a spurious positive impact of being first-born on educationWe have checked that this problem is of no consequence for our results6
The summary statistics of our sample are presented in Table 1 The detaileddescription of variables is relegated to Appendix 1 We found more than 8000 indexpersons (from more than 3100 distinct families) older than 24 in 2001 with at leastone other sibling and whose mother has completed her fertility This is to be con-trasted with Conley and Glauber (2004) who use larger sample from the US Censusbut focus only on children under the age of 20 living at home
The main dependent variablemdashyears of completed educationmdashhas an average of1262 years7 About 82 percent of those selected index persons have at least 12 years ofeducation that is to say have completed high school8 Our measure of earningsmdashloghourly wage in 2001mdashshows an average corresponding to $145hour However theinformation on hourly wages or salary income is not available for most index persons
The average age in our sample is 39 About half of respondents are male and 47percent are White The average number of siblings is 486 This high number is con-sistent with the PSID oversampling minorities and low-income populations Fifty-sixpercent of the index persons have all their siblings reporting and 60 percent have boththeir parents reporting their childbirth history
We improved our analysis by including important observed family level-effects thatvary across parity family income and whether the mother is married Wheneveravailable we constructed the corresponding information for each of the first 14 yearsof life of each index person9 The main limitation is that information on familyincome cannot be recovered for many index individuals
Lastly we include two variables describing characteristics of index individualsrsquo par-ents namely education (11 years for both mother and father on average) and the age ofthe parents at birth of index persons (26 for mothers and 29 for fathers on average)
III Methods and Results
A The First-Born Effect
We first use an OLS estimation with robust standard errors clustered by family unit(identified by the mother) which relaxes the independence assumption between the
6 The regressions presented in this article contain age controls that separate cohort from birth order effects 7 A more appropriate variable would be education at age 25 However the number of observations avail-able would drop considerably and we would not be able to run estimations by sibling size All of our otherresults when running estimations that control for siblings size hold when replacing education with educationat age 25 for those where such information can be traced8 A negligible fraction of those who declare a certain education level at some point in their life declare lesseducation later Removing such observations did not alter our results We therefore choose the latest educa-tion level reported as our variable of interest9 We then ran our regressions using the average of these variables for three age groups 1ndash6 7ndash14 and1ndash14 For each age group the averages are respectively calculated only if the information is present in atleast half of the years of the age group
The Journal of Human Resources760
error terms and requires only that the observations be independent across clusters10
In Table 2 we first test the hypothesis that being early in the birth order implies a dis-tinct advantage that is entirely due to the higher probability of coming from a smallfamily
Columns 1 and 2 of Table 2 reject that claim but help us understand why it mayhave been made In Column 1 we omit the number of siblings therefore the signif-icant coefficient on first-born reflects not only the birth order effect but also the prob-ability of coming from a small family In Column 2 the inclusion of the number ofsiblings leaves the coefficient on first-born insignificant
In Column 3 we include age of the mother at childbirth and find a positive andhighly significant effect of being first-born on years of education This effect is con-firmed when including the fatherrsquos characteristics in Column 4 where both a father anda mother report Often not all siblings report this is especially the case for large fam-ilies To check if we are biasing our results by including such families in Column 5 werestrict our attention to families with complete information on all siblings The findingsare similar there too further showing that they could not be driven by selective attri-tion within families by birth order In all specifications we find a stronger effect amongWhite families
The results presented here are for the impact of being first-born in families of morethan one child This particular procedure takes advantage of the full size of our sam-ple and can be useful when there are not enough observations to run separate estima-tions for different siblingsrsquo sizes11 We see that it allows us to reveal a significant androbust birth order effect
However we still obtain similar results when looking at individual birth ordereffects by siblingsrsquo size in Table 3 where all specifications include age of the motherat childbirth Although large families show higher birth order point estimates theeffect is present in two-sibling families as well Note that the coefficient on first-bornis only weakly significant in Column 4mdashfamilies of five siblingsmdashlikely because ofthe small sample size
The reason why the inclusion of the age of the mother at childbirth makes the coef-ficient on first-born larger in magnitude and more significant is clear The age of themother at childbirth is mechanically positively correlated with birth order and evenmore strongly across large families Conversely we see that it is positively correlatedwith a childrsquos education Then if having a high birth order carries a negative impacton education the two effects of birth order and age of the mother at childbirth com-pete against one another Therefore the coefficient on first-born in Table 2 Column 2reflects an omitted variable bias The results hold for both males and females formothers with or without more than a high school education We also found that spac-ing between births be it that of the first-born child with respect to the second-born orto the last-born child does not alter the conclusions either Additional OLS regres-sions confirmed that the effect is significantly present among White families of any
10 We also used random effects procedures but because they yield almost identical results as those withthe family clustered standard errors those are not reported11 For example we found a significant birth-order effect when considering separately mothers who firstgave birth early and mothers who first gave birth ldquolaterdquo (using various definitions of ldquoearlyrdquo and ldquolaterdquo) yetwe do not have enough observations to split the sample by maternal age and individual siblings size
Kantarevic and Mechoulan 761Ta
ble
2O
LS
Reg
ress
ion
wit
h D
epen
dent
Var
iabl
e E
duca
tion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
016
20
012
028
80
239
026
8(0
068
)
(00
69)
(00
72)
(0
098
)
(00
84)
To
tal n
umbe
r of
sib
lings
minus01
04minus0
121
minus01
08minus0
125
(00
15)
(0
015
)
(00
19)
(0
029
)
Age
of
mot
her
at c
hild
birt
h0
058
006
10
065
(00
05)
(0
011
)
(00
08)
d[
Mal
e]minus0
205
minus02
1minus0
226
minus01
86minus0
159
(00
47)
(0
046
)
(00
46)
(0
058
)
(00
57)
A
ge0
121
015
90
162
014
30
087
(00
27)
(0
027
)
(00
27)
(0
039
)
(00
40)
A
ge2
minus00
01minus0
001
minus00
01minus0
001
minus00
03(0
000
3)
(0
000
3)
(0
000
3)
(0
001
)
(00
001)
d[W
hite
]0
119
minus00
03minus0
099
minus02
95minus0
107
(00
72)
(00
73)
(00
71)
(00
87)
(0
098
)d[
first
-bor
n] times
d[W
hite
]0
126
019
30
184
028
60
172
(00
92)
(00
92)
(0
092
)
(01
15)
(0
104
)M
othe
rrsquos
educ
atio
n0
213
019
80
199
011
40
236
(00
12)
(0
012
)
(00
12)
(0
017
)
(00
18)
d[
all s
iblin
gs r
epor
t]0
261
009
60
181
014
4(0
068
)
(00
69)
(00
69)
(0
089
)d[
both
par
ents
rep
ort]
052
30
553
052
00
533
(00
63)
(0
062
)
(00
61)
(0
081
)
Fath
errsquos
edu
catio
n0
125
(00
12)
A
ge o
f fa
ther
at c
hild
birt
h0
006
(00
09)
Con
stan
t6
713
671
75
073
516
25
848
(05
28)
(05
31)
(0
541
)
(07
75)
(0
776
)
R2
015
780
1691
018
890
2009
019
82N
umbe
r of
obs
erva
tions
792
87
928
792
87
766
454
1N
umbe
r of
fam
ily c
lust
ers
311
23
112
311
21
869
173
2
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 759
education is decreasing over cohorts which is of course untrue according to the USCensus Because a first-born is older than other siblings by definition this alonecould in theory produce a spurious positive impact of being first-born on educationWe have checked that this problem is of no consequence for our results6
The summary statistics of our sample are presented in Table 1 The detaileddescription of variables is relegated to Appendix 1 We found more than 8000 indexpersons (from more than 3100 distinct families) older than 24 in 2001 with at leastone other sibling and whose mother has completed her fertility This is to be con-trasted with Conley and Glauber (2004) who use larger sample from the US Censusbut focus only on children under the age of 20 living at home
The main dependent variablemdashyears of completed educationmdashhas an average of1262 years7 About 82 percent of those selected index persons have at least 12 years ofeducation that is to say have completed high school8 Our measure of earningsmdashloghourly wage in 2001mdashshows an average corresponding to $145hour However theinformation on hourly wages or salary income is not available for most index persons
The average age in our sample is 39 About half of respondents are male and 47percent are White The average number of siblings is 486 This high number is con-sistent with the PSID oversampling minorities and low-income populations Fifty-sixpercent of the index persons have all their siblings reporting and 60 percent have boththeir parents reporting their childbirth history
We improved our analysis by including important observed family level-effects thatvary across parity family income and whether the mother is married Wheneveravailable we constructed the corresponding information for each of the first 14 yearsof life of each index person9 The main limitation is that information on familyincome cannot be recovered for many index individuals
Lastly we include two variables describing characteristics of index individualsrsquo par-ents namely education (11 years for both mother and father on average) and the age ofthe parents at birth of index persons (26 for mothers and 29 for fathers on average)
III Methods and Results
A The First-Born Effect
We first use an OLS estimation with robust standard errors clustered by family unit(identified by the mother) which relaxes the independence assumption between the
6 The regressions presented in this article contain age controls that separate cohort from birth order effects 7 A more appropriate variable would be education at age 25 However the number of observations avail-able would drop considerably and we would not be able to run estimations by sibling size All of our otherresults when running estimations that control for siblings size hold when replacing education with educationat age 25 for those where such information can be traced8 A negligible fraction of those who declare a certain education level at some point in their life declare lesseducation later Removing such observations did not alter our results We therefore choose the latest educa-tion level reported as our variable of interest9 We then ran our regressions using the average of these variables for three age groups 1ndash6 7ndash14 and1ndash14 For each age group the averages are respectively calculated only if the information is present in atleast half of the years of the age group
The Journal of Human Resources760
error terms and requires only that the observations be independent across clusters10
In Table 2 we first test the hypothesis that being early in the birth order implies a dis-tinct advantage that is entirely due to the higher probability of coming from a smallfamily
Columns 1 and 2 of Table 2 reject that claim but help us understand why it mayhave been made In Column 1 we omit the number of siblings therefore the signif-icant coefficient on first-born reflects not only the birth order effect but also the prob-ability of coming from a small family In Column 2 the inclusion of the number ofsiblings leaves the coefficient on first-born insignificant
In Column 3 we include age of the mother at childbirth and find a positive andhighly significant effect of being first-born on years of education This effect is con-firmed when including the fatherrsquos characteristics in Column 4 where both a father anda mother report Often not all siblings report this is especially the case for large fam-ilies To check if we are biasing our results by including such families in Column 5 werestrict our attention to families with complete information on all siblings The findingsare similar there too further showing that they could not be driven by selective attri-tion within families by birth order In all specifications we find a stronger effect amongWhite families
The results presented here are for the impact of being first-born in families of morethan one child This particular procedure takes advantage of the full size of our sam-ple and can be useful when there are not enough observations to run separate estima-tions for different siblingsrsquo sizes11 We see that it allows us to reveal a significant androbust birth order effect
However we still obtain similar results when looking at individual birth ordereffects by siblingsrsquo size in Table 3 where all specifications include age of the motherat childbirth Although large families show higher birth order point estimates theeffect is present in two-sibling families as well Note that the coefficient on first-bornis only weakly significant in Column 4mdashfamilies of five siblingsmdashlikely because ofthe small sample size
The reason why the inclusion of the age of the mother at childbirth makes the coef-ficient on first-born larger in magnitude and more significant is clear The age of themother at childbirth is mechanically positively correlated with birth order and evenmore strongly across large families Conversely we see that it is positively correlatedwith a childrsquos education Then if having a high birth order carries a negative impacton education the two effects of birth order and age of the mother at childbirth com-pete against one another Therefore the coefficient on first-born in Table 2 Column 2reflects an omitted variable bias The results hold for both males and females formothers with or without more than a high school education We also found that spac-ing between births be it that of the first-born child with respect to the second-born orto the last-born child does not alter the conclusions either Additional OLS regres-sions confirmed that the effect is significantly present among White families of any
10 We also used random effects procedures but because they yield almost identical results as those withthe family clustered standard errors those are not reported11 For example we found a significant birth-order effect when considering separately mothers who firstgave birth early and mothers who first gave birth ldquolaterdquo (using various definitions of ldquoearlyrdquo and ldquolaterdquo) yetwe do not have enough observations to split the sample by maternal age and individual siblings size
Kantarevic and Mechoulan 761Ta
ble
2O
LS
Reg
ress
ion
wit
h D
epen
dent
Var
iabl
e E
duca
tion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
016
20
012
028
80
239
026
8(0
068
)
(00
69)
(00
72)
(0
098
)
(00
84)
To
tal n
umbe
r of
sib
lings
minus01
04minus0
121
minus01
08minus0
125
(00
15)
(0
015
)
(00
19)
(0
029
)
Age
of
mot
her
at c
hild
birt
h0
058
006
10
065
(00
05)
(0
011
)
(00
08)
d[
Mal
e]minus0
205
minus02
1minus0
226
minus01
86minus0
159
(00
47)
(0
046
)
(00
46)
(0
058
)
(00
57)
A
ge0
121
015
90
162
014
30
087
(00
27)
(0
027
)
(00
27)
(0
039
)
(00
40)
A
ge2
minus00
01minus0
001
minus00
01minus0
001
minus00
03(0
000
3)
(0
000
3)
(0
000
3)
(0
001
)
(00
001)
d[W
hite
]0
119
minus00
03minus0
099
minus02
95minus0
107
(00
72)
(00
73)
(00
71)
(00
87)
(0
098
)d[
first
-bor
n] times
d[W
hite
]0
126
019
30
184
028
60
172
(00
92)
(00
92)
(0
092
)
(01
15)
(0
104
)M
othe
rrsquos
educ
atio
n0
213
019
80
199
011
40
236
(00
12)
(0
012
)
(00
12)
(0
017
)
(00
18)
d[
all s
iblin
gs r
epor
t]0
261
009
60
181
014
4(0
068
)
(00
69)
(00
69)
(0
089
)d[
both
par
ents
rep
ort]
052
30
553
052
00
533
(00
63)
(0
062
)
(00
61)
(0
081
)
Fath
errsquos
edu
catio
n0
125
(00
12)
A
ge o
f fa
ther
at c
hild
birt
h0
006
(00
09)
Con
stan
t6
713
671
75
073
516
25
848
(05
28)
(05
31)
(0
541
)
(07
75)
(0
776
)
R2
015
780
1691
018
890
2009
019
82N
umbe
r of
obs
erva
tions
792
87
928
792
87
766
454
1N
umbe
r of
fam
ily c
lust
ers
311
23
112
311
21
869
173
2
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources760
error terms and requires only that the observations be independent across clusters10
In Table 2 we first test the hypothesis that being early in the birth order implies a dis-tinct advantage that is entirely due to the higher probability of coming from a smallfamily
Columns 1 and 2 of Table 2 reject that claim but help us understand why it mayhave been made In Column 1 we omit the number of siblings therefore the signif-icant coefficient on first-born reflects not only the birth order effect but also the prob-ability of coming from a small family In Column 2 the inclusion of the number ofsiblings leaves the coefficient on first-born insignificant
In Column 3 we include age of the mother at childbirth and find a positive andhighly significant effect of being first-born on years of education This effect is con-firmed when including the fatherrsquos characteristics in Column 4 where both a father anda mother report Often not all siblings report this is especially the case for large fam-ilies To check if we are biasing our results by including such families in Column 5 werestrict our attention to families with complete information on all siblings The findingsare similar there too further showing that they could not be driven by selective attri-tion within families by birth order In all specifications we find a stronger effect amongWhite families
The results presented here are for the impact of being first-born in families of morethan one child This particular procedure takes advantage of the full size of our sam-ple and can be useful when there are not enough observations to run separate estima-tions for different siblingsrsquo sizes11 We see that it allows us to reveal a significant androbust birth order effect
However we still obtain similar results when looking at individual birth ordereffects by siblingsrsquo size in Table 3 where all specifications include age of the motherat childbirth Although large families show higher birth order point estimates theeffect is present in two-sibling families as well Note that the coefficient on first-bornis only weakly significant in Column 4mdashfamilies of five siblingsmdashlikely because ofthe small sample size
The reason why the inclusion of the age of the mother at childbirth makes the coef-ficient on first-born larger in magnitude and more significant is clear The age of themother at childbirth is mechanically positively correlated with birth order and evenmore strongly across large families Conversely we see that it is positively correlatedwith a childrsquos education Then if having a high birth order carries a negative impacton education the two effects of birth order and age of the mother at childbirth com-pete against one another Therefore the coefficient on first-born in Table 2 Column 2reflects an omitted variable bias The results hold for both males and females formothers with or without more than a high school education We also found that spac-ing between births be it that of the first-born child with respect to the second-born orto the last-born child does not alter the conclusions either Additional OLS regres-sions confirmed that the effect is significantly present among White families of any
10 We also used random effects procedures but because they yield almost identical results as those withthe family clustered standard errors those are not reported11 For example we found a significant birth-order effect when considering separately mothers who firstgave birth early and mothers who first gave birth ldquolaterdquo (using various definitions of ldquoearlyrdquo and ldquolaterdquo) yetwe do not have enough observations to split the sample by maternal age and individual siblings size
Kantarevic and Mechoulan 761Ta
ble
2O
LS
Reg
ress
ion
wit
h D
epen
dent
Var
iabl
e E
duca
tion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
016
20
012
028
80
239
026
8(0
068
)
(00
69)
(00
72)
(0
098
)
(00
84)
To
tal n
umbe
r of
sib
lings
minus01
04minus0
121
minus01
08minus0
125
(00
15)
(0
015
)
(00
19)
(0
029
)
Age
of
mot
her
at c
hild
birt
h0
058
006
10
065
(00
05)
(0
011
)
(00
08)
d[
Mal
e]minus0
205
minus02
1minus0
226
minus01
86minus0
159
(00
47)
(0
046
)
(00
46)
(0
058
)
(00
57)
A
ge0
121
015
90
162
014
30
087
(00
27)
(0
027
)
(00
27)
(0
039
)
(00
40)
A
ge2
minus00
01minus0
001
minus00
01minus0
001
minus00
03(0
000
3)
(0
000
3)
(0
000
3)
(0
001
)
(00
001)
d[W
hite
]0
119
minus00
03minus0
099
minus02
95minus0
107
(00
72)
(00
73)
(00
71)
(00
87)
(0
098
)d[
first
-bor
n] times
d[W
hite
]0
126
019
30
184
028
60
172
(00
92)
(00
92)
(0
092
)
(01
15)
(0
104
)M
othe
rrsquos
educ
atio
n0
213
019
80
199
011
40
236
(00
12)
(0
012
)
(00
12)
(0
017
)
(00
18)
d[
all s
iblin
gs r
epor
t]0
261
009
60
181
014
4(0
068
)
(00
69)
(00
69)
(0
089
)d[
both
par
ents
rep
ort]
052
30
553
052
00
533
(00
63)
(0
062
)
(00
61)
(0
081
)
Fath
errsquos
edu
catio
n0
125
(00
12)
A
ge o
f fa
ther
at c
hild
birt
h0
006
(00
09)
Con
stan
t6
713
671
75
073
516
25
848
(05
28)
(05
31)
(0
541
)
(07
75)
(0
776
)
R2
015
780
1691
018
890
2009
019
82N
umbe
r of
obs
erva
tions
792
87
928
792
87
766
454
1N
umbe
r of
fam
ily c
lust
ers
311
23
112
311
21
869
173
2
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 761Ta
ble
2O
LS
Reg
ress
ion
wit
h D
epen
dent
Var
iabl
e E
duca
tion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
016
20
012
028
80
239
026
8(0
068
)
(00
69)
(00
72)
(0
098
)
(00
84)
To
tal n
umbe
r of
sib
lings
minus01
04minus0
121
minus01
08minus0
125
(00
15)
(0
015
)
(00
19)
(0
029
)
Age
of
mot
her
at c
hild
birt
h0
058
006
10
065
(00
05)
(0
011
)
(00
08)
d[
Mal
e]minus0
205
minus02
1minus0
226
minus01
86minus0
159
(00
47)
(0
046
)
(00
46)
(0
058
)
(00
57)
A
ge0
121
015
90
162
014
30
087
(00
27)
(0
027
)
(00
27)
(0
039
)
(00
40)
A
ge2
minus00
01minus0
001
minus00
01minus0
001
minus00
03(0
000
3)
(0
000
3)
(0
000
3)
(0
001
)
(00
001)
d[W
hite
]0
119
minus00
03minus0
099
minus02
95minus0
107
(00
72)
(00
73)
(00
71)
(00
87)
(0
098
)d[
first
-bor
n] times
d[W
hite
]0
126
019
30
184
028
60
172
(00
92)
(00
92)
(0
092
)
(01
15)
(0
104
)M
othe
rrsquos
educ
atio
n0
213
019
80
199
011
40
236
(00
12)
(0
012
)
(00
12)
(0
017
)
(00
18)
d[
all s
iblin
gs r
epor
t]0
261
009
60
181
014
4(0
068
)
(00
69)
(00
69)
(0
089
)d[
both
par
ents
rep
ort]
052
30
553
052
00
533
(00
63)
(0
062
)
(00
61)
(0
081
)
Fath
errsquos
edu
catio
n0
125
(00
12)
A
ge o
f fa
ther
at c
hild
birt
h0
006
(00
09)
Con
stan
t6
713
671
75
073
516
25
848
(05
28)
(05
31)
(0
541
)
(07
75)
(0
776
)
R2
015
780
1691
018
890
2009
019
82N
umbe
r of
obs
erva
tions
792
87
928
792
87
766
454
1N
umbe
r of
fam
ily c
lust
ers
311
23
112
311
21
869
173
2
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources762
Tabl
e 3
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Edu
cati
on
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
027
50
698
071
50
534
091
5(0
104
)
(01
36)
(0
185
)
(03
16)
(02
36)
d[
seco
nd-b
orn]
043
40
463
033
40
578
(01
17)
(0
16)
(02
82)
(01
95)
d[
thir
d-bo
rn]
017
10
212
036
8(0
14)
(02
47)
(01
75)
d[
four
th-b
orn]
minus00
120
466
(02
14)
(01
52)
d[
fifth
-bor
n]0
221
(01
33)
Age
of
the
mot
her
at c
hild
birt
h0
048
007
90
067
006
80
07(0
012
)
(00
13)
(0
013
)
(00
23)
(0
013
)
d[M
ale]
minus02
87minus0
115
minus00
35minus0
34
minus00
33(0
102
)
(00
91)
(01
07)
(01
31)
(0
087
)
Age
021
70
190
156
007
50
167
(00
56)
(0
057
)
(00
49)
(0
044
)(0
057
)
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 763
Age
20
002
000
20
002
3times
10minus4
000
2(7
times10
minus4)
(7
times10
minus4)
(6
times10
minus4)
(5
times10
minus4)
(8times
10minus4
)
d[W
hite
]0
119
minus01
244
times10
minus5minus0
03
minus01
14(0
12)
(01
3)(0
13)
(01
81)
(01
37)
Mot
herrsquo
s ed
ucat
ion
025
70
250
179
012
40
182
(00
25)
(0
026
)
(00
23)
(0
035
)
(00
22)
d[
all s
iblin
gs r
epor
t]0
147
021
2minus0
066
035
10
21(0
154
)(0
136
)(0
128
)(0
178
)
(01
49)
d[bo
th p
aren
ts r
epor
t]0
241
061
20
755
054
20
371
(01
18)
(0
118
)
(01
26)
(0
189
)
(01
27)
C
onst
ant
333
92
694
425
86
607
412
(11
48)
(1
184
)
(10
11)
(1
293
)
(14
15)
R
20
185
021
019
011
40
127
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources764
size greater than one whereas it is only present within large families among BlacksTherefore the ethnic differential disappears when considering large families only
As noted earlier a causal interpretation of the age of the mother at childbirth wouldhinge on the assumption of its exogeneity Without instrumental variables or a treat-ment versus control quasi experiment it is difficult to draw conclusions12 The age ofthe mother at childbirth itself positively correlated with birth order could easilyproxy for other unobserved variables such as level of human capital and parentalresources13
To address this problem our fixed-effect estimation (Table 4a and b) removes fam-ily characteristics and unobserved family-level heterogeneity14 Family fixed effectsaddress family unobservables to the extent that they are constant over time While wetry to incorporate observables that vary across birth order to affirm the robustness ofour results we are constrained by the availability of such variables in the data set
Unfortunately the coefficients on age or on age of the mother at childbirth are unin-formative in those fixed effects regressions Deviations from family means for ageconvey the same information as deviations from family means for age of mother atchildbirth We thus do not provide separate estimations with age and age of motherat childbirth The age of the mother at first childbirth is certainly relevant but here itis differenced out Still to assess this issue better we ran separate regressions split-ting the sample by maternal age15 To summarize the following results are robust toexcluding mothers who first gave birth as teens but we do not have enough observa-tions to meaningfully run the fixed effects regressions by sibling size on that lattergroup
In Tables 4a and 4b the fixed effects estimations that only control for age and gen-der confirm the previous results for the most part16 We also provide estimations includ-ing the marital status of the mother17 during the childrsquos first 14 years18 The results donot change by much19 Clearly the suggestion that first-borns are most likely to live
12 Also while it is possible in the context of larger samples to instrument for siblings sizemdashusing twinbirths (Black Devereux and Salvanes 2005) or using the fact that parents of two same sex children are morelikely to have a third child (Conley and Glauber 2004)mdashone cannot instrument for birth order per se13 This is further evidenced by the fact that including a dummy variable indicating whether the mother wasmarried at the time of childbirth instead of (and obviously also along with) age of mother at childbirth alsoresults in highly significant birth order coefficients Results are available upon request14 However it is worth noting that those fixed effects do not solve all endogeneity issues For example itmay be the case that first-born ldquoqualityrdquo is affecting subsequent fertility We thank an anonymous referee forpointing out this caveat15 We thank an anonymous referee for this suggestion16 In Column 1mdashfamilies of two siblingsmdashthe coefficient on first-born becomes significant at the 10 per-cent level when including index persons of 23 and 24 years of age suggesting the nonsignificance whenrestricting at age 25 stems from a small sample size Separate FE regressions for White and Black familiesconfirmed the ethnic differentials found earlier17 We tried two definitions number of years marriednumber of years considered in the age group and = 1if continuously married over the years considered in the age group 0 otherwise Since the results on birthorder do not change qualitatively with either of those we only report the results with the latter definition18 We also ran similar estimations with different age ranges and obtained similar results19 Because the information on marital status is retrospective we do not lose any observation by includingthis covariate Unfortunately this is not the case when adding average family income or average employmentstatus of the mother during the childrsquos first years
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 765
Table 4aFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Not Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0216 0437 0683 0594 0477(0181) (0206) (0265) (0379) (0224)
d[second- 0282 0412 0421 0199born] (0141) (0214) (0323) (0195)
d[third- 0138 0361 0055born] (0159) (0261) (0172)
d[fourth- minus0031 0181born] (0207) (0149)
d[fifth- minus0012born] (0125)
Observations 1422 1743 1477 922 2487groups 934 835 562 388 573
Table 4bFixed Effects Linear Regression with Dependent Variable Education (AllCoefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0224 0436 0696 0585 0492(0181) (0206) (0267) (0379) (0226)
d[second-born] 028 0423 0413 0212(0141) (0216) (0323) (0197)
d[third-born] 0146 0363 0063(0159) (0261) (0173)
d[fourth-born] minus0025 0188(0207) (0149)
d[fifth-born] minus0016(0125)
Mother minus0196 minus0167 0112 0381 minus0105Continuously (0315) (0221) (0221) (0274) (0178)married aged 1ndash14
Number of 1422 1743 1477 999 2487observations
Number of 934 835 562 328 573groups
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources766
their critical development years in a stable household as opposed to later-borns whomay experience the divorce of their parents cannot entirely explain the first-bornadvantage At the same time the persistence of birth-order effects naturally poses theproblem of their origin
The literature is not able to distinguish between different theories on the topic ofbirth order For example schooling circumstances play a large role in educational out-comes and may be related to birth order20 Our analysis is limited in the sense that itcannot discriminate between many competing hypotheses on why birth order appearsto be important21
Nevertheless we checked whether what appears as a first-born advantage predom-inantly comes from financial constraints for example parents sending their first-bornto college and running out of money for the following siblings Conley offers the fol-lowing argument ldquo[I]n terms of parental investment the cup starts to run dry as wego down the line Parental resources it appears are allotted on a first come first-served basisrdquo22 Yet if it turns out that first-borns perform better beforehand then atheory based on budget constraints cannot fully account for our results In Tables 5ndash7we estimate the probability of completing high school following the same methodol-ogy as in Tables 2ndash4 We find that first-borns have a higher probability of completinghigh school than later born siblings
Specifically Table 5 shows again that the first-born effect is not an artifact of fam-ily size that it increases in magnitude and significance when including age of motherat birth that it is robust to including characteristics of father and to restricting thesample to families in which all siblings report Table 6 shows that these results alsohold when regressions are estimated separately by family size (except for families offive presumably because of the small sample size) Tables 7a and 7b are the counter-parts of Tables 4a and 4b Fixed effects regressions controlling for age and gendersupport the results found in Tables 5 and 623
Also we estimated education at age 18 conditional on high school completion (at18 or older) to see if later-borns are more likely to repeat grades which would sup-port a theory of birth-order effects based on cognitive development differences Wedid not find any evidence for this However the small sample size resulting fromselecting index persons with available information at age 18 warrants some caution
Finally we found evidence among White families only that conditional on com-pleting high school first-borns are more likely to receive postsecondary educationYet for all races conditional on postsecondary education we found no clear advan-tage to being first-born24 In summary financial constraints do seem to play a role butsome factors early in life contribute to the first-born premium puzzle
20 We thank an anonymous referee for this point21 We refer the reader to the survey of those theories presented in Black Devereux and Salvanes (2005)22 Conley (2004) p 6923 The results held when including motherrsquos marital status We ran into the same small size problems whenadding family income and motherrsquos employment status for different age ranges of each child The ethnic dif-ferential disappears when considering all families (but persists when focusing on smaller families) suggest-ing that some of the birth order effect among White families comes from postsecondary education24 Results are available from the authors
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 767
Tabl
e 5
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
004
40
024
005
50
039
004
4(0
014
)
(00
14)
(00
14)
(0
018
)
(00
17)
To
tal n
umbe
r of
0
014
001
60
011
001
2si
blin
gs(0
003
)
(00
03)
(0
004
)
(00
05)
A
ge o
f th
e m
othe
r 0
006
000
70
005
at c
hild
birt
h(0
000
1)
(0
002
)
(00
01)
d[
Mal
e]0
047
004
80
049
004
70
037
(00
09)
(0
009
)
(00
09)
(0
009
)
(00
10)
A
ge0
024
002
90
029
003
20
023
(00
04)
(0
004
)
(00
04)
(0
007
)
(00
07)
A
ge2
000
020
0003
000
020
0003
000
02(5
times10
minus5)
(5
times10
minus5)
(5
times10
minus5)
(8
times10
minus5)
(8
times10
minus5)
d[
Whi
te]
000
50
012
002
30
042
001
9(0
014
)(0
014
)(0
014
)(0
017
)
(00
19)
d[fir
st-b
orn]
timesd
001
5minus0
005
minus00
060
011
000
6[W
hite
](0
017
5)(0
017
)(0
017
)(0
021
)(0
021
)M
othe
rrsquos
educ
atio
n0
027
002
60
026
001
50
026
(00
02)
(0
002
)
(00
02)
(0
003
)
(00
03)
d[
com
plet
e in
fo
003
50
094
002
20
029
on a
ll si
blin
gs]
(00
13)
(0
012
)
(00
13)
(00
15)
d[bo
th p
aren
ts r
epor
t]0
090
094
009
00
097
(00
12)
(0
012
)
(00
12)
(0
016
)
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources768
Tabl
e 5
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
Fath
errsquos
edu
catio
n0
011
(00
02)
A
ge o
f fa
ther
minus0
001
at c
hild
birt
h(0
002
)C
onst
ant
010
50
104
028
80
241
012
9(0
089
)(0
089
)(0
094
)
(01
35)
(01
41)
R2
008
790
0943
010
180
0885
008
55N
umbe
r of
obs
erva
tions
792
87
928
792
84
766
454
1N
umbe
r of
fam
ily
311
23
112
311
21
869
173
2cl
uste
rs
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 769
Tabl
e 6
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Hig
h Sc
hool
Com
plet
ion
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
003
80
084
009
003
10
122
(00
18)
(0
025
)
(00
36)
(0
053
)(0
049
)
d[se
cond
-bor
n]0
071
008
2times
10minus4
002
2(0
022
)
(00
31)
(0
051
)(0
044
)d[
thir
d-bo
rn]
003
10
012
003
5(0
028
)(0
041
)(0
037
)d[
four
th-b
orn]
006
10
041
(00
37)
(00
33)
d[fif
th-b
orn]
000
7(0
028
)A
ge o
f th
e m
othe
r at
chi
ldbi
rth
000
30
004
000
90
008
001
1(0
002
)(0
002
)(0
003
)
(00
04)
(0
003
)
d[M
ale]
minus00
3minus0
041
000
7minus0
094
minus00
82(0
016
)(0
016
)
(00
2)(0
026
)
(00
18)
A
ge0
028
002
80
051
001
20
037
(00
07)
(0
009
)
(00
1)
(0
008
)(0
011
)
Age
23
times10
minus43
times10
minus45
times10
minus48
times10
minus54times
10minus4
(9times
10minus5
)
(10minus5
)
(10minus5
)
(9times
10minus5
)(1
0minus4)
d[
Whi
te]
001
20
124
004
90
033
002
2(0
021
)(0
023
)(0
026
)(0
034
)(0
028
)M
othe
rrsquos
educ
atio
n0
024
002
50
027
001
80
027
(00
04)
(0
004
)
(00
05)
(0
005
)
(00
04)
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources770
Tabl
e 6
(con
tinu
ed)
(1)
(2)
(3)
(4)
(5)
d[al
l sib
lings
rep
ort]
minus00
110
03minus0
034
005
90
037
(00
25)
(00
24)
(00
24)
(00
34)
(00
3)d[
both
par
ents
rep
ort]
004
50
076
012
50
088
009
8(0
019
)
(00
22)
(0
027
)
(00
36)
(0
026
)
Con
stan
t0
115
025
40
927
002
60
644
(01
6)(0
2)
(02
)
(02
34)
(02
61)
R
20
076
008
40
138
007
80
088
Num
ber
of o
bser
vatio
ns1
398
170
51
444
959
242
2N
umbe
r of
fam
ily c
lust
ers
913
811
542
308
538
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
)(1
)ndash(5
) F
amili
es o
f 2
3 4
5 a
nd 6
and
abo
ve s
iblin
gs r
espe
ctiv
ely
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Table 7aFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Not Including Marital Status ofMother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0132 0076 0124(0029) (0037) (0051) (0073)
(0051)d[second-born] 0064 0107 0039 0029
(0026) (0041) (0062) (0045)d[third-born] 0048 0061 0047
(003) (005) (0039)d[fourth-born] minus0054 0049
(004) (0034)d[fifth-born] 0004
(0029)Observations 1422 1743 1477 999 2487
groups 934 835 562 328 573
Table 7bFixed Effects Linear Regression with Dependent Variable High School Completion(All Coefficients Deviation from Family Means) Including Marital Status of Mother
(1) (2) (3) (4) (5)
d[first-born] 0033 0089 0134 0075 0129(0029) (0037) (0051) (0073) (0052)
d[second-born] 0063 0109 0039 0033(0026) (0041) (0062) (0045)
d[third-born] 0049 0061 0049(003) (0051) (0039)
d[fourth-born] minus0053 0051(004) (0034)
d[fifth-born] 0004(0028)
Mother minus0001 minus0058 0019 0025 minus0035continuously (0051) (004) (0042) (0053) (0041)married age 1ndash14
Observations 1422 1743 1477 999 2487Groups 934 835 562 328 573
(1)ndash(5) all mothers have completed their fertility (age gt 44) all respondents assumed to have completed theireducation (age gt 24) (1)ndash(5) Families of 2 3 4 5 and 6 and above siblings respectively 10 percent sig-nificance 5 percent significance 1 percent significance Robust standard errors clustered by familyNo estimation was run with age because including both age and age of mother at birth is redundant in a fam-ily fixed effects regression The regressions also include age of mother at birth and an indicator for males
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources772
B The ldquoLast-Born Effectrdquo in Large Families
We now test the hypothesis that within large (more than five siblings) families the last-borns do better than the middle-borns who in turn do worst There is some support in theliterature for a so-called ldquocrunch in the middlerdquo effect25 This nonlinear pattern was alsoadvanced by Hanushek (1992) and in the context of time allocation by Lindert (1977)
There are many ways to replicate these findings Short of enough observations for eachfamily size when family size is very large the variables of interest chosen in Table 8are dummies indicating whether a child is first-born and whether a child is last-born
When omitting the age of mother at childbirth in Column 1 the first-born coeffi-cient is insignificant as earlier but the coefficient on last born is positive and signifi-cant Notice that this does not happen when we run the same regression on smallerfamilies However in Column 2 once the age of the mother at childbirth is factoredin we find that being last-born confers no advantage but that being first-born does
The fixed effects estimation (Column 3) confirms the absence of any upward trendfrom middle-born to last-born26 The interpretation of those results is similar to theones presented earlier and the same qualifications apply27
IV Birth Order and Earnings
Because education is a key in determining earnings we should like-wise find a similar birth order effect on earnings Our sample is more limited becausewe only have information on earnings for heads or wives who declare working (about36 percent of our initial sample) Nonetheless Table 9 shows that the results on hourlyearnings display the same patterns as for education namely a nonsignificant effect ofbirth order when age of the mother at birth is omitted and a significant effect when itis included Curiously for non-White non-Black families we noticed the persistenceof a robust first-born effect on earnings after controlling for education This deservesfuture research Note that with only a few hundred observations on hourly earningsfor each sibling size we cannot run meaningful OLS or fixed effects estimations bysiblings size28
V Conclusion
We have shown how the omission of the age of the mother at child-birth effect results in an underestimation of the impact of being first-born and an over-
25 ldquoFor almost as long as sociologists have been studying who gets ahead they have found that kids from largefamilies do more poorly than those from small ones There is however one exception to this Last-born childrenfrom very large families seem to fare quite well the middle kids do worstrdquo Conley (2004) p 66 and p 6926 Adding whether the mother was continuously married during the childrenrsquos first years does not changethe results qualitatively and similar small size problems arose when adding family income and employmentstatus of the mother for different age ranges of each child Results are available from the authors27 Restricting the sample to both parents present at childbirth yields similar results However we cannotdo the same with large families with complete information on all siblings The sample becomes too small28 Fixed effects estimations for the entire sample confirm the OLS results though
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 773
Table 8Regression with Dependent Variable Completed Education (Large Families)
Family OLS Fixed Effects
(1) (2) (3)
d[first-born] 0078 0427 0084(0187) (0195) (0039)
d[lastborn] 0343 minus0047 0008(0126) (0138) (0032)
d[White] minus0059 minus0164(0159) (0149)
d[first-born] times d[White] 0099 0098 minus0001(0322) (0321) (0059)
d[last-born] times d[White] minus0052 minus0039 minus0057(0198) (0195) (0047)
Total number of siblings minus0059 minus009(0031) (0033)
Age of the mother at 0055 0002childbirth (0011) (0002)
d[Male] minus0322 minus0331 minus0085(0089) (0087) (0017)
Age 0168 0172(0066) (0068)
Age2 minus0002 minus0002(00008) (00001)
Motherrsquos education 0175 0180(0022) (0021)
d[all siblings report] 0112 0176(0151) (0151)
d[both parents report] 0449 0429(0129) (0126)
Constant 6755 5207 0707(1317) (1329) (0066)
R2 01114 01292 001Number of observations 2422 2422 2487Number of family clusters 538 538 573
(1)ndash(3) all mothers have completed their fertility (age gt 44) all respondents assumed to have completedtheir education (age gt 24) all respondent from families gt 5 siblings Robust standard errors clustered byfamily 10 percent significance 5 percent significance 1 percent significance
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources774
Tabl
e 9
OL
S R
egre
ssio
n w
ith
Dep
ende
nt V
aria
ble
Log
Hou
rly
Wag
e in
200
1
(1)
(2)
(3)
(4)
(5)
d[fir
st-b
orn]
010
20
067
010
60
126
014
3(0
043
)
(00
44)
(00
45)
(0
057
)
(00
51)
To
tal n
umbe
r of
sib
lings
minus00
21minus0
024
minus00
24minus0
04
(00
07)
(0
007
)
(00
09)
(0
014
)
Age
of
the
mot
her
at c
hild
birt
h0
008
000
80
009
(00
02)
(0
005
)(0
003
)
d[M
ale]
030
00
299
029
80
346
029
(00
245)
(00
24)
(0
024
)
(00
29)
(0
03)
Age
005
90
067
006
50
068
007
8(0
013
)
(00
13)
(0
013
)
(00
17)
(0
021
)
Age
2minus0
000
5minus0
000
6minus0
001
minus00
005
minus00
01(0
000
2)
(0
000
2)
(0
000
2)
(0
000
2)
(00
002)
d[W
hite
]0
144
010
90
096
001
90
117
(00
35)
(0
036
)
(00
36)
(0
043
)(0
046
)
d[fir
st-b
orn]
timesd[
Whi
te]
minus00
86minus0
062
minus00
65minus0
094
minus01
28(0
054
)(0
054
)(0
054
)(0
064
)(0
061
)
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 775
Mot
herrsquo
s ed
ucat
ion
004
80
044
004
30
021
004
5(0
006
)
(00
06)
(0
006
)
(00
08)
(0
009
)
d[co
mpl
ete
info
on
all s
iblin
gs]
010
20
063
007
10
095
(00
32)
(0
035
)(0
036
)
(00
44)
d[
both
par
ents
rep
ort]
009
20
098
009
70
169
(00
29)
(0
029
)
(00
29)
(0
037
)
Fath
errsquos
edu
catio
n0
045
(00
06)
Age
of
fath
er a
t chi
ldbi
rth
000
2(0
004
)C
onst
ant
023
50
254
010
5minus0
262
minus01
62(0
263
)(0
261
)(0
264
)(0
342
)(0
400
)R
20
1594
016
290
1658
022
060
1759
Num
ber
of o
bser
vatio
ns3
000
300
03
000
205
91
962
Num
ber
of f
amily
clu
ster
s1
575
157
51
575
107
51
015
(1)ndash
(5)
all
mot
hers
hav
e co
mpl
eted
thei
r fe
rtili
ty (
age
gt44
) a
ll re
spon
dent
s as
sum
ed to
hav
e co
mpl
eted
thei
r ed
ucat
ion
(age
gt24
) an
d ha
ve a
t lea
st o
ne o
ther
sib
ling
(4)
d[b
oth
pare
nts
repo
rt]
=1
and
(5)
d[c
ompl
ete
info
on
all s
iblin
gs]
=1
1
0 pe
rcen
t sig
nific
ance
5 p
erce
nt s
igni
fican
ce
1
per
cent
sig
nific
ance
Rob
ust s
tand
ard
erro
rs c
lust
ered
by
fam
ily
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
The Journal of Human Resources776
Appendix 1Description of the Variables
Variable Description
Years of completed educationa Years of education reported in the most recent yearCompleted high schoola = 1 if years of completed education greater than
or equal to 12Hourly earningse = hourly earnings in 2001 if the index person is
a head or a wife of a household and missing otherwise
Agea = the age of index person based on the year of birth
Malea = 1 if the gender of index person is maleWhiteb = 1 if the race of mother of index person is White
or if the race of mother of index person is missing but the race of father is White
Number of siblingsc The total number of childbirths reported by the mother of index person if mother older than 44 in the last year in which she reported otherwise set to missing
Birth orderc (first-born etc) The birth order of index personFamily incomeb = Total income of the household The average
family income is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+ years for ages 7ndash14 and 7+ years for ages 1ndash14)
Mother marriedd = 1 the mother is continuously married during the relevant period and 0 if not The average marital status of mother is calculated only if it is available for at least 50 percent of years in the relevant time period (3+ years for ages 1ndash6 4+years for ages 7ndash14 and 7+ years for ages 1ndash14)
Information on all siblings = 1 if all siblings present in the sample and reportBoth parents report the = 1 if both the mother and father of index person
childbirth report the birth of index person
Data Sourcesa Individual PSID fileb Family PSID filec Childbirth and Adoption History Filed Marriage History Filee Hours of Work and Wages File
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74
Kantarevic and Mechoulan 777
estimation of the impact of being last-born At this point however the age of themother at childbirth should be interpreted broadly as a proxy for a set of maternalinputs Most importantly fixed-effects estimations confirmed the presence of a sig-nificant positive first-born effect and the absence of either specific middle-born orlast-born effects among large families First-born children on average retain an advan-tage acquired early on throughout both their educational and professional life Thiseffect is enhanced within White families
Our data do not permit to contribute to the recent debate over the impact of familysize on educational attainment Therefore while we tentatively agree with Hanushek(1992) that smaller family sizes may be responsible for a rise in scholastic perfor-mances over cohorts in the United States we would like to emphasize that this effectis compounded by a corresponding increase in the proportion of first-born children
References
Birdsall Nancy 1979 ldquoSiblings and Schooling in Urban Columbiardquo Dissertation YaleUniversity Department of Economics
Behrman Jere R 1986 ldquoBirth Order Nutrition and Health Intra-Household Allocation inRural Indiardquo University of Pennsylvania Unpublished
Behrman Jere R and Paul Taubman 1986 ldquoBirth Order Schooling and Earningsrdquo Journalof Labor Economics 4(3)S121ndashS45
Black Sandra E Paul J Devereux and Kjell G Salvanes 2005 ldquoThe More the Merrier TheEffect of Family Composition on Childrenrsquos Educationrdquo Quarterly Journal of Economics120(2)669ndash700
Booth Alison L and Hiau Joo Kee 2005 ldquoBirth Order Matters The Effect of Family Sizeand Birth Order on Educational Attainmentrdquo IZA working paper No 1713
Bronars Stephen G and Jeff Grogger 1994 ldquoThe Economic Consequences of UnwedMotherhood Using Twin Births as a Natural Experimentrdquo American Economic Review84(5)1141ndash56
Conley Dalton 2004 The Pecking Order Pantheon Books New YorkConley Dalton and Rebecca Glauber 2004 ldquoParental Educational Investment and Childrenrsquos
Academic Risk Estimates of the Impact of Sibship Size and Birth Order from ExogenousVariation in Fertilityrdquo Journal of Human Resources This issue
Geronimus Arline T Sanders Korenman and Marianne M Hillemeier 1994 ldquoDoes YoungMaternal Age Affect Child Development Evidence from Cousin Comparisons in theUnited Statesrdquo Population and Development Review 20(3)585ndash609
Hanushek Eric A 1992 ldquoThe Trade-off between Child Quantity and Qualityrdquo Journal ofPolitical Economy 100(1)84ndash117
Hofferth Sandra L and Lori Reid 2002 ldquoEarly Childbearing and Childrenrsquos Achievementand Behavior over Timerdquo Perspectives on Sexual and Reproductive Health 34(1)41ndash49
Kessler Daniel 1991 ldquoBirth Order Family Size and Achievement Family Structure andWage Determinationrdquo Journal of Labor Economics 9(4)413ndash26
Lindert Peter H 1977 ldquoSibling Position and Achievementrdquo Journal of Human Resources12(2)198ndash219
Lopez-Turley Ruth N 2003 ldquoAre Children of Young Mothers Disadvantaged Because ofTheir Motherrsquos Age or Family Backgroundrdquo Child Development 74(2)465ndash74