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Household Studies

Paul LambertStirling University

Prepared for “Longitudinal Data Analysis for Social Science Researchers: Introductory Seminar”, Royal Statistical Society, 28th April 2006

April 2006: LDA 2

Quantitative Longitudinal Household Studies

1) Repeated cross-sectional household surveys

2) Longitudinal surveys with household information

3) Household panel surveys The BHPS in international context The BHPS in the UK

April 2006: LDA 3

Longitudinal Households?

• .. device to talk about the BHPS

• Improving data quality• Reliability: Household sharers’ records

• Context: Household sharers’ data

• Longitudinal questions• Household life-courses

• Household transitions

• Intra-relations: similarity and dependence

April 2006: LDA 4

1) Repeated cross-sectional household surveys

for example..

• UK Census

• Labour Force Survey• General Household Survey • Family Resources Survey

??Annual population survey

April 2006: LDA 5

2) Longitudinal Surveys with Household Information

• Cohort studies (see later)– Birth Cohort Studies– Youth Cohort Study

• Census Longitudinal Studies (see later)• Individual panel studies

• ELSA• Re-contact studies

• Individual level repeated cross-sections• Social attitudes surveys• ISSP / WVS / ESS• British Election Studies

April 2006: LDA 6

3) Household Panel Surveys

• The BHPS

• The BHPS in international context

• The BHPS in the UK

April 2006: LDA 7

The British Household Panel Survey 1991-2006

Panel study of 5k households re-contacted annually since 1991

Major UK research investment

For lots more introductions, see: http://www.longitudinal.stir.ac.uk/

April 2006: LDA 8

The ‘Essex’ BHPS

ISER - Institute for Social and Economic Research

ULSC - UK Longitudinal Studies Centre• Design, coordinate, release, analyse and promote

the BHPS Data supplied by UK Data Archive at University

of Essex Online documentation and support:

http://iserwww.essex.ac.uk/ulsc/bhps/doc/

April 2006: LDA 9

Annual survey since 1991

• Sample re-interviewed once a year

• Each new panel is a ‘wave’

• Interviews start each September

• Datasets updated and re-released annually

• Government funding to at least 2009

April 2006: LDA 10

BHPS data file structures

C o m b in edlife h is to ry f ile

Y o u th in te rv ie ws1 1 -1 5yrs , 19 9 4 ->

In te r- a n d p re-w a ve life h is to ry f iles

A d ult ind ivid u alin te rview s

H ouseho ldda ta collec tion

W ave-on -w avep ane l da tase ts

In d ex link ingfile s

C o re B H PSp ane l da tase ts

(ann u al up d ate)

D e rived n e tin co m e va ria b les

T e a ch ingd a tase ts

S o urce B H P S reco rds

April 2006: LDA 11

You’ll most likely use..

• Adult individual interviews• All adults within household contribute and

individual record

• Youth records• All 11-14’s within houshold

• Combined life-history files • Oriented around event history analyses (durations)

April 2006: LDA 12

Sampling design

• W1 (1991): Stratified random sample of 5,500 households

14,000 ‘OSM’ household members Later waves: trace all OSM’s; their

descendants; and their household sharers (TSM’s)

NB: longitudinal trace of individuals and their surrounding household, but not of ‘longitudinal households’

April 2006: LDA 13

• W7-11 -> ECHP supplement (low incomes) • W9- -> Scottish and Welsh boosts• W11- -> Northern Irish boostsFuture: possible minority group boosts?• These are important!!

– affect representativeness– use of weights is complicated– catches every user out at least once…

Extension samples

April 2006: LDA 14

BHPS sampling structure

OSM TSM ECHP boost

Scot. boost

Wales boost

N. Irel boost

Total sample

Tot adults interviewed

Wave: A: 1991 13,840 13,840 10,264 B: 1992 12,567 584 13,151 9,845 C: 1993 12,219 885 13,104 9,600 D: 1994 11,821 1030 12,851 9,481 E: 1995 11,425 1124 12,549 9,249 F: 1996 11,412 1308 12,720 9,438 G: 1997 11,251 1301 2490 15,042 11,193 H: 1998 11,161 1300 2374 14,835 10,906 I: 1999 10,996 1337 2258 3397 3577 21,565 15,624 J: 2000 10,773 1481 2193 3584 3573 21,604 15,605 K: 2001 10,624 1610 2125 3518 3523 5188 26,588 18,869 L: 2002 10,470 1664 3329 3385 4589 23,437 16,599

BHPS Unbalanced panel & Data Management: Below data may have come from 6 different BHPS source files

Wave Person Person-level Vars 1 1 1 38 1 36

1 2 2 34 2 0

1 3 2 6 9 -

2 1 1 39 1 38

2 2 2 35 1 16

3 1 1 40 1 36

3 2 2 36 1 18

3 3 2 8 9 -

N_w=3 N_p=3

April 2006: LDA 16

The household structure of the BHPS

• All adults within a household are interviewed• Clustering analysis issues

• Person groups?

• All persons within a household are ennumerated• Children records

• Rising 16’s

• Siblings and migration

BHPS Household analysis possibilities are exciting but complex..

April 2006: LDA 17

. . Individuals . .

Person Groups

Regions PSU1 PSU2 PSU3 Wave 1

Wave 2

Wave 3

. .

.

. . .

.

. . .

.

.

Interviewers : W 1, 3 : Interviewer1 Interviewer2 Interviewer3 W 2 only : Interviewer2 Interviewer3 Interviewer1

April 2006: LDA 18

The BHPS in International Context

• Part of: – ECHP (1997-2001)

– CHER (1991-2000)

– PACO (1991-1998)

– CNEF (1991->)

– EU-SILC (2003 onwards: under-discussion)

– Numerous stand-alone comparative projects

• Source project : US PSID • Use of comparable questionnaire design

April 2006: LDA 19

Cross-national comparisons

• Focussed studies • McGinnity, F. (2002) “The Labour-Force Participation of the Wives of

Unemployed Men: Comparing Britian and West Germany” European Sociological Review, 18(4)473-488

Benefits system influences wives participation in Britian, not Germany

• Broader comparisons• Robson, K. and Berthoud, R. (2003) “Teenage Motherhood in Europe: A

Multi-Country Analysis of Socioeconomic Outcomes” European Sociological Review, 19(5)451-466

Substantial variations in economic circumstances of teenage mothers, and their family structures, across Europe

April 2006: LDA 20

The BHPS in the UK

• Major ESRC investment

• 5500 households nationally

• Scottish, Welsh and Northern Irish boost samples 1999 / 2001

April 2006: LDA 21

Assets of the BHPS

1) Large scale panel dataset!• Answer questions on processes, transitions,

state dependence• Offers longitudinal controls• Extensive methodological resources,

support, validation

2) Household information• Full information of family sharers• Complex but tractable handling

April 2006: LDA 22

Assets of the BHPS

3) The wYOUTH records• Unique datasource on 11-15yrs• Can link to family / trace to adulthood

4) Occupational information• Detail on own jobs, histories, spells• Detail on family, parental, friends jobs

April 2006: LDA 23

Assets of the BHPS

5) High quality income information

• Range of sources

• Imputation procedures / validation work

6) Subpopulaton analyses

• Plausible to identify and analyse distinct groupings, eg home nations

• But not others, eg ethnicity

April 2006: LDA 24

Drawbacks with the BHPS

1) Complexity of the data records

• Puts off potential users

• Forces advanced users to specialise

2) Short term panel coverage

• Doesn’t yet span long enough spells

April 2006: LDA 25

Drawbacks with the BHPS

3) Dropout and item non-response

• A little of the first

• A lot of the second

4) Interviewers & Panel conditioning

• Panel conditioning very likely?

April 2006: LDA 26

Drawbacks with the BHPS

5) Regional sampling bases

• Endogeneity to labour market?

• Imposition on generalisations, eg more from Dundee than Glasgow .

6) Complex clustering• BHPS individual level response = Ytijkl

April 2006: LDA 27

Three modes of analysis

1) (Repeated) Cross-sectional

2) Panel

3) Life history

April 2006: LDA 28

Associations with transitions between subjective social class categories (I) Aggregate Transitions between subjective position:

all adults, N: not working class; W: working class; F-N F-W I-N I-W

A-N 2350 675 2085 753 A-W 659 1767 585 1735 F-N 2179 621 F-A 509 1886

Example: Descriptive analysis of panel data

April 2006: LDA 29

Associations with transitions in subjective class category Associations with transition to ‘working class’: W-I and N –A/F (no such transition for 4311 adults, transition to working class for 1061) Eta-correl Phi association CAMSIS advantage in..† Manual job A +0.07** Fathers job -0.12** Manual job F +0.10** Wave A job -0.07** Manual job J +0.10** Wave F job -0.10** Move to manual +0.06** Wave J job -0.10** Move to non-mnl +0.03 J job – {0.02} Vote labour J {-0.00} (A or F) Unfair rich +0.02* † : Working males only

April 2006: LDA 30

SUMMARY

• BHPS many complexities

• But more potential uses

• Eclectic resources

• Greater use seems sensible