11 comparison of several multivariate means shyh-kang jeng department of electrical engineering/...

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1 1 Comparison of Several Comparison of Several Multivariate Means Multivariate Means Shyh-Kang Jeng Shyh-Kang Jeng Department of Electrical Department of Electrical Engineering/ Engineering/ Graduate Institute of Graduate Institute of Communication/ Communication/ Graduate Institute of Networking Graduate Institute of Networking and Multimedia and Multimedia

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Page 1: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

1111

Comparison of Several Comparison of Several Multivariate MeansMultivariate Means

Shyh-Kang JengShyh-Kang JengDepartment of Electrical Engineering/Department of Electrical Engineering/

Graduate Institute of Communication/Graduate Institute of Communication/

Graduate Institute of Networking and Graduate Institute of Networking and MultimediaMultimedia

Page 2: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

2222

Paired ComparisonsPaired ComparisonsMeasurements are recorded under Measurements are recorded under different sets of conditions different sets of conditions See if the responses differ See if the responses differ significantly over these setssignificantly over these setsTwo or more treatments can be Two or more treatments can be administered to the same or similar administered to the same or similar experimental unitsexperimental unitsCompare responses to assess the Compare responses to assess the effects of the treatmentseffects of the treatments

Page 3: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

3333

Example 6.1: Example 6.1: Effluent Data from Two LabsEffluent Data from Two Labs

Page 4: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

4444

Single Response (Univariate) CaseSingle Response (Univariate) Case

n

std

n

std

ttHH

tns

Dt

ND

njXXD

dn

dn

n

n

d

dj

jjj

)2/()2/(

for interval confidence )%1(100

)2/( if0:offavor in 0:Reject

:/

),(:

,,2,1,

11

110

1

2

21

Page 5: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

5555

Multivariate Extension: NotationsMultivariate Extension: Notations

2tment under trea variable

2tment under trea 2 variable

2tment under trea 1 variable

--------------------------------

1tment under trea variable

1tment under trea 2 variable

1tment under trea 1 variable

2

22

12

1

21

11

pX

X

X

pX

X

X

jp

j

j

jp

j

j

Page 6: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

6666

Result 6.1Result 6.1

n

jjjd

n

jj

pnpd

dpj

jpjjj

jpjpjp

jjj

jjj

nn

Fpn

pnnT

njN

DDD

XXD

XXD

XXD

11

,12

21

21

22212

12111

'1

1,

1

)(

)1(:'

,,2,1),,(:

',,,

DDDDSDD

δDSδD

ΣδD

D

Page 7: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

7777

Test of Hypotheses and Test of Hypotheses and Confidence RegionsConfidence Regions

n

s

ptd

n

sF

pn

pnd

Fpn

pn

Fpn

pnnT

HH

ddd

ii dnii

dpnpii

pnpd

pnpd

jpjjj

2

1

2

,

,1

,12

10

21'

2:,)(

)1(:

)()1(

':regions Confidence

)()1(

'

if 0: offavor in 0:Reject

sdifference observed:,,,

δdSδd

dSd

δδ

d

Page 8: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

8888

Example 6.1: Check Measurements Example 6.1: Check Measurements from Two Labsfrom Two Labs

zero includesBoth

32.255.71,-or 11/61.41847.927.13:

74.3,46.22or 11/26.19947.936.9:

0:Reject

47.9)05.0(9

1026.13

27.13

36.9

0026.00012.0

0012.00055.027.1336.911

61.41838.88

38.8826.199,

27.13

36.9

2

1

0

9,2

2

2

1

δ

Sd

H

F

T

d

dd

Page 9: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

9999

Experiment Design for Experiment Design for Paired ComparisonsPaired Comparisons

. . .

. . .

1 2 3 n

Treatments1 and 2assigned atrandom

Treatments1 and 2assigned atrandom

Treatments1 and 2assigned atrandom

Treatments1 and 2assigned atrandom

Page 10: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

10101010

Alternative ViewAlternative View

xCCSCCxCSCSxCdCxd

C

SS

SSS

x

12

)2(

2221

1211

2222111211

''',',,

100|100

|

010|010

001|001

,,,,,,,'

nT

xxxxxx

djj

pp

pp

Page 11: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

11111111

Repeated Measures Design for Repeated Measures Design for Comparing MeasurementsComparing Measurements

qq treatments are compared with treatments are compared with respect to a single response variablerespect to a single response variable

Each subject or experimental unit Each subject or experimental unit receives each treatment once over receives each treatment once over successive periods of timesuccessive periods of time

Page 12: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

12121212

Example 6.2: Treatments in an Example 6.2: Treatments in an Anesthetics ExperimentAnesthetics Experiment

19 dogs were initially given the drug 19 dogs were initially given the drug pentobarbitol followed by four pentobarbitol followed by four treatmentstreatments

Halothane

Present

Absent

CO2 pressureLow High

12

3 4

Page 13: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

13131313

Example 6.2: Sleeping-Dog DataExample 6.2: Sleeping-Dog Data

Page 14: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

14141414

Contrast MatrixContrast Matrix

XμX

qq

j

jq

j

j

j Enj

X

X

X

2

1

1

31

21

2

1

1001

0101

0011

)(,,2,1,

Page 15: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

15151515

Test for Equality of Treatments in a Test for Equality of Treatments in a Repeated Measures DesignRepeated Measures Design

)()1(

)1)(1(''

if Reject

0: vs.0: ofTest

matrixcontrast :),,(:

1,112

0

10

qnq

q

Fqn

qnnT

H

HH

N

xCCSCxC

CμCμ

CΣμX

Page 16: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

16161616

Example 6.2: Contrast MatrixExample 6.2: Contrast Matrix

1111

1111

1111

ninteractio COH

contrast CO

contrast Halothane

23241

24231

2143

C

Page 17: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

17171717

Example 6.2: Test of HypothesesExample 6.2: Test of Hypotheses

0:Reject

94.1005.0)1(

)1)(1(

116''

44.755754.91462.927

54.91484.519592.1098

62.92792.109832.9432

',

79.12

05.60

31.209

99.487863.449944.406535.2295

32.685198.530349.2943

14.796342.3568

29.2819

,

89.502

26.479

63.404

21.368

0

1,1

12

xCCSCxC

CSCxC

Sx

H

Fqn

qn

nT

qnq

Page 18: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

18181818

Example 6.2: Simultaneous Example 6.2: Simultaneous Confidence IntervalsConfidence Intervals

97.6579.1219

44.755794.1079.12

"ninteractio"CO-H

70.545.6019

84.519594.1005.60

influence pressure CO

70.7331.20919

)05.0(16

)3(18

influence halothane ofContrast

2

2

1'1

16,32143

Scc

Fxxxx

Page 19: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

19191919

Comparing Mean Vectors from Comparing Mean Vectors from Two PopulationsTwo Populations

Populations: Sets of experiment Populations: Sets of experiment settingssettingsWithout explicitly controlling for unit-Without explicitly controlling for unit-to-unit variability, as in the paired to-unit variability, as in the paired comparison casecomparison caseExperimental units are randomly Experimental units are randomly assigned to populationsassigned to populationsApplicable to a more general Applicable to a more general collection of experimental unitscollection of experimental units

Page 20: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

20202020

Assumptions Concerning the Assumptions Concerning the Structure of DataStructure of Data

21

21

2222111211

22

22221

11

11211

normal temultivaria are spopulationBoth

:small and when sassumptionFurther

,,, oft independen are ,,,

covariance and r mean vecto with population

variate from sample random:,,,

covariance and r mean vecto with population

variate from sample random:,,,

21

2

1

ΣΣ

XXXXXX

Σμ

XXX

Σμ

XXX

nn

p

p

nn

n

n

Page 21: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

21212121

Pooled Estimate of Pooled Estimate of Population Covariance MatrixPopulation Covariance Matrix

221

21

21

1

21

12222

11111

21

2222

11

1111

2

1

2

1

2

''

1'

1'

21

2

1

SS

xxxxxxxx

S

Σxxxx

Σxxxx

nn

n

nn

n

nn

n

n

n

jjj

n

jjj

pooled

n

jjj

n

jjj

Page 22: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

22222222

Result 6.2Result 6.2

1,

21

21

2121

1

212121

2

222221

111211

21

2

1

1

2

as ddistribute is

11'

),(:,,,

),(:,,,

pnnp

pooled

pn

pn

Fpnn

pnn

nnT

N

N

μμXX

SμμXX

ΣμXXX

ΣμXXX

Page 23: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

23232323

Proof of Result 6.2Proof of Result 6.2

1,

21

21

1

21

2

2121

2/1

21

12121

2/1

21

2

22211

122111

2121

22

212

11

111

21

21

21

21

21

21

1

2:),(

2

)()',0(

11

'11

)(:11

:1,:1

)11

,(:

1111

pnnppnn

p

pooled

nn

nn

p

nn

Fpnn

pnnN

nn

WN

nn

nnT

Wnn

WnWn

nnN

nnnn

Σ0Σ

Σ

μμXX

SμμXX

ΣSS

ΣSΣS

Σμμ

XXXXXX

Page 24: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

24242424

Wishart DistributionWishart Distribution

)'|'(:')|(:

)|(:

)|(:),|(:

:Properties

definite positive:

21

2

)|(

2121

2211

1

2/)1(4/)1(2/)1(

2/tr2/)2(

1

21

21

1

CΣΣCACCACΣAA

ΣAAAA

ΣAAΣAA

A

Σ

AΣA

mm

mm

mm

p

i

nppnp

pn

n

WW

W

WW

in

ew

Page 25: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

25252525

Test of HypothesisTest of Hypothesis

ΣXX

XXXXXX

XX

μμXX

δxxSδxx

δμμδμμ

2121

212211

21

2121

1,21

21

021

1

21021

2

02110210

11)Cov()Cov(

)Cov(),Cov(),Cov()Cov(

)Cov(

)( Note

)(1

2

11'if

: offavor in :Reject

21

nn

E

Fpnn

pnn

nnT

HH

pnnp

pooled

Page 26: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

26262626

Example 6.3: Comparison of Soaps Example 6.3: Comparison of Soaps Manufactured in Two WaysManufactured in Two Ways

65.025.0,15.125.0

25.0)05.0(1

211

'290.0957.0,697.1

'957.0290.0,303.5

: of rseigenvecto and sEigenvalue

2.0

9.1,

51

12

98

49

98

49

41

12,

9.3

2.10,

61

12,

1.4

3.8

50

21

1,21

21

21

12

11

2121

2211

21

21

pnnp

pooled

pooled

Fpnn

pnn

nn

nn

e

e

S

xxSSS

SxSx

Page 27: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

27272727

Example 6.3Example 6.3

Page 28: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

28282828

Result 6.3: Simultaneous Result 6.3: Simultaneous Confidence IntervalsConfidence Intervals

poolediiii

ii

pooled

pnnp

snn

cXX

μ

nnc

Fpnn

pnnc

,21

21

21

21

2121

1,21

212

11)(

by covered be will ,particularIn

allfor )('cover will

11')('

)(1

221

aμμa

aSaXXa

Page 29: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

29292929

Example 6.4: Electrical Usage of Example 6.4: Electrical Usage of Homeowners with and without ACs Homeowners with and without ACs

26.6)05.0(97

)2(98

3.636615.21505

5.215057.10963

2

1

2

1

55,5.559647.19616

7.196160.8632,

0.355

0.130

45,4.731074.23823

4.238233.13825,

6.556

4.204

97,22

221

21

21

1

122

111

Fc

nn

n

nn

n

n

n

pooled SSS

Sx

Sx

Page 30: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

30303030

Example 6.4: Electrical Usage of Example 6.4: Electrical Usage of Homeowners with and without ACsHomeowners with and without ACs

5.3287.47or

3.6366155

1

45

126.6)0.3556.556(:

1.1277.21or

7.1096355

1

45

126.6)0.1304.204(:

intervals confidence ussimultaneo 95%

2212

2212

2111

2111

Page 31: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

31313131

Example 6.4: Example 6.4: 95% Confidence Ellipse95% Confidence Ellipse

Page 32: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

32323232

Bonferroni Simultaneous Bonferroni Simultaneous Confidence IntervalsConfidence Intervals

poolediinnii snnp

txx ,21

22121

11

2:

21

Page 33: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

33333333

Result 6.4Result 6.4

aSSaxxa

μμa

μμxx

SSμμxx

μμ

22

11

221

21

22121

1

22

11

2121

21

21

11')('

:'for intervals confidence usSimultaneo

)(

11'

:for ellipsoid confidence 100%

large are and

nn

nn

pnpn

p

p

Page 34: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

34343434

Proof of Result 6.4Proof of Result 6.4

2211

22121

1

22

11

2121

22

11

2121

22

11

2121

2121

~,~

:

11'

11,nearly :

11CovCovCov

SΣSΣ

μμXX

ΣΣμμXX

ΣΣμμXX

ΣΣXXXX

μμXX

p

p

nn

nnN

nn

E

Page 35: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

35353535

RemarkRemark

nnnnnn

nn

nnn

nn

n

nnn

pooled

1111

2

11

1112

1

2

1

If

21

2122

11

21

SSS

SSSS

Page 36: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

36363636

Example 6.5 Example 6.5

063.0

041.011 :ncombinatiolinear Critical

99.5)05.0(66.1511

'

0:

4.27375.8,or 15.264299.56.201:

127.121.7,or 17.46499.54.74:

15.264208.886

08.88617.46411

Data 6.4 Example

21

1

22

11

2221

1

22

11

212

210

2212

2111

22

11

xxSS

xxSSxx

μμ

SS

nn

nnT

H

nn

Page 37: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

3737

Multivariate Behrens-Fisher Multivariate Behrens-Fisher ProblemProblem

Test Test HH00: : 11--22=0 =0

Population covariance matrices are Population covariance matrices are unequalunequal

Sample sizes are not largeSample sizes are not large

Populations are multivariate normalPopulations are multivariate normal

Both sizes are greater than the Both sizes are greater than the number of variablesnumber of variables

3737

Page 38: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

3838

Approximation of Approximation of TT22 Distribution Distribution

3838

2121

2

121

22

11

21

22

11

2

1,

2121

1

22

11

21212

),min(

111tr

111tr

1

1

11'

nnnn

nnn

nnn

n

pp

Fp

p

nnT

i

ii

ii

i

pp

SSS

SSS

μμXXSSμμXX

Page 39: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

3939

Confidence RegionConfidence Region

3939

)(1

11'

1,

2121

1

22

11

2121

ppFp

p

nnμμxxSSμμxx

Page 40: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

4040

Example 6.6Example 6.6

Example 6.4 dataExample 6.4 data

4040rejected is 0:,32.666.15

32.612.36.76

2.155)05.0(

1

6.77

354.0092.0

060.0224.0111

646.0092.0

060.0776.0111

2102

1,

1

22

11

22

1

22

11

11

μμ

SSS

SSS

HT

Fp

p

nnn

nnn

pp

Page 41: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

41414141

Example 6.10: Nursing Home DataExample 6.10: Nursing Home Data

Nursing homes can be classified by Nursing homes can be classified by the owners: private (271), non-profit the owners: private (271), non-profit (138), government (107)(138), government (107)Costs: nursing labor, dietary labor, Costs: nursing labor, dietary labor, plant operation and maintenance plant operation and maintenance labor, housekeeping and laundry labor, housekeeping and laundry laborlaborTo investigate the effects of To investigate the effects of ownership on costsownership on costs

Page 42: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

42424242

One-Way MANOVAOne-Way MANOVA

tlysignificandiffer components

mean which not, if and, same, theare vectors

mean population he whether teinvestigat toused is

VAriance) Of ANalysis ate(MultivariMANOVA

,,, : Population

,,, :2 Population

,,, :1 Population

21

22221

11211

2

1

ggngg

n

n

g XXX

XXX

XXX

Page 43: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

43434343

Assumptions about the DataAssumptions about the Data

normal temultivaria is populationEach

matrix

covariancecommon a have spopulation All

tindependen

are spopulationdifferent from sample Random

,,2,1,mean with

population a from sample random :,,,21

Σ

μ

XXX

g

n

Page 44: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

44444444

Univariate ANOVAUnivariate ANOVA

xxxxxx

nNeeX

H

H

g

NXXX

jj

g

jjj

g

g

n

0),,0(:,

0:

rizationReparamete

: hypothesis Null

,,2,1

),( from sample random:,,,

1

2

210

210

221

Page 45: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

45454545

Univariate ANOVAUnivariate ANOVA

)SS()SS()SS()(SS

)SS()SS()(SS

0

2

1 1

2

1

2221

1 1

2

1 1

2

1

2

1 1

2

1

22

1

2

1

222

restrmeanobs

g n

jj

gg n

jj

restrcor

g n

jj

gg n

jj

n

jj

n

jj

n

jj

jjj

xxxxnxnnnx

xxxxnxx

xxxxnxx

xx

xxxxxxxxxx

Page 46: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

46464646

Univariate ANOVAUnivariate ANOVA

Page 47: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

47474747

Univariate ANOVAUnivariate ANOVA

trres

res

restr

gngg

res

tr

g

F

gn

gF

H

SSSS

SS

SS/SS1

1

)(

/SS

)1/SS

if levelat 0:Reject

,1

1

210

Page 48: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

48484848

Concept of Degrees of FreedomConcept of Degrees of Freedom

gg

g

ggnnn

xxxxxx

xxxxxx

nnnnxxxxxg

uuu

y

2211

21

21221111

1

1

0

0

0

0

0

0

1

1

0

0

0

0

0

0

1

1

vectorTreatment

d.f. :,,,,,,,'21

Page 49: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

49494949

Concept of Degrees of FreedomConcept of Degrees of Freedom

gn

xxxxxxx

gx

g

g

gg

g

g

: of d.f.

,,,by spanned hyperplane thelar toperpendicu

vector Residual

1 d.f. : r mean vecto

vector treatment thelar toperpendicu is

d.f.:,,,by spanned

hyperplane on the all are andvector Treatment

1,,1

21

2211

21

21

e

uuu

uuu1ye

1

1

uuu

1

uuu1

Page 50: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

50505050

Examples 6.7 & 6.8Examples 6.7 & 6.8

level 1% at the rejected is 0:

27.13)01.0(5.195/10

2/78

/SS

)1/(SS

53-3)2(3 d.f.,10SS

213 d.f. ,78SS

128SS,216SS

011

11

121

222

33

444

444

44

444

213

20

969

3210

5,2

H

Fgn

gF

res

tr

res

tr

meanobs

Page 51: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

51515151

MANOVAMANOVA

g n

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g n

j

g

jj

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g

pj

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n

n

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1 1 1

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Page 52: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

52525252

MANOVAMANOVA

Page 53: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

53535353

MANOVAMANOVA

small toois

'

'

lambda s Wilk'if 0:Reject

111

'

1 1

1 1*

210

2211

1 1

g n

jjj

g n

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g

gg

g n

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W

H

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xxxxW

Page 54: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

54545454

Distribution of Wilk’s LambdaDistribution of Wilk’s Lambda

Page 55: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

55555555

Test of Hypothesis for Large SizeTest of Hypothesis for Large Size

)(ln2

1

if level cesignificanat Reject

:ln2

1

large, is and trueis If

2)1(

0

2)1(

*

0

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gp

gpn-

H

gpn-

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W

Page 56: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

56565656

Popular MANOVA Statistics Used Popular MANOVA Statistics Used in Statistical Packagesin Statistical Packages

1

1

1

*

)( of eigenvalue maximum

rootlargest sRoy'

)( tracePillai

traceHotelling-Lawley

lambda sWilk'

WBW

WBB

BW

WB

W

tr

tr

Page 57: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

57575757

Example 6.9Example 6.9

2722448200SSSSSSSS,

798

04

723

2161078128SSSSSSSS,

213

20

969

5

4,

5

4,

2

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3

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Page 58: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

58585858

Example 6.8Example 6.8

14972792639:Total

1(-1)031(-2)(-2)(-1)1:Residual

-123(-2)3(-3)(-3)2(-1)43 :Treatment

160548 :Mean

products Cross

110

22

321

333

33

111

555

55

555

798

04

723

011

11

121

222

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444

444

44

444

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20

969

Page 59: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

59595959

Example 6.9Example 6.9

Page 60: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

60606060

Example 6.9Example 6.9

0

8,412),1(2

*

*

*

Reject

01.7)01.0()01.0(19.8

13

138

0385.0

0385.01

1

11

0385.0

7211

1188

241

110

H

FF

g

gn

gng

WB

W

Page 61: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

61616161

Example 6.10: Nursing Home DataExample 6.10: Nursing Home Data

Nursing homes can be classified by Nursing homes can be classified by the owners: private (271), non-profit the owners: private (271), non-profit (138), government (107)(138), government (107)Costs: nursing labor, dietary labor, Costs: nursing labor, dietary labor, plant operation and maintenance plant operation and maintenance labor, housekeeping and laundry labor, housekeeping and laundry laborlaborTo investigate the effects of To investigate the effects of ownership on costsownership on costs

Page 62: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

62626262

Example 6.10Example 6.10

Page 63: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

63636363

Example 6.10Example 6.10

304.0230.0610.0584.0

235.0453.0821.0

225.1111.1

475.3

'

'380.0102.0519.0136.2

538.6394.0428.2581.9

484.1633.0695.1

200.8408.4

962.182

)1()1()1(

1

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332211

332211

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Page 64: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

64646464

Example 6.10Example 6.10

analysesboth by Reject

09.20)01.0()01.0(

76.132ln)2/)(1(

analysis eapproximat or,

51.28/)01.0()01.0(

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Page 65: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

65656565

Bonferroni Intervals for Bonferroni Intervals for Treatment EffectsTreatment Effects

2/)1(

)(

11ˆˆVar

)()(

111

11VarˆˆVar

ˆˆ,ˆ

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gpgm

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Page 66: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

66666666

Result 6.5: Bonferroni Intervals for Result 6.5: Bonferroni Intervals for Treatment EffectsTreatment Effects

nngn

w

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k

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)1(

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)1(least at confidenceWith

Page 67: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

67676767

Example 6.11: Example 6.10 DataExample 6.11: Example 6.10 Data

019.0,021.0,026.0,058.0: and

for intervals confidence ussimultaneo 95%

025.0,061.0or 0.006142.870.043-

for interval confidence ussimultaneo 95%

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t

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Page 68: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

6868

Test for Equality of Covariance Matrices

With g populations, null hypothesis H0: 1 = 2 = . . . = g =

Assume multivariate normal populationsLikelihood ratio statistic for testing H0

ggpooled

n

pooled

nnn

SSS

S

S

111

111

2/)1(

Page 69: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

6969

Box’s M-Test

)( if Reject

)1)(1(2

1

eapproximat :)1(

)1)(1(6

132

1

1

1

1

ln1ln1ln2

20

2

2

CH

gpp

MuC

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pp

nnu

nnM pooled

SS

Page 70: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

7070

Example 6.12Example 6.10 - nursing home data

CH

C

M

u

nnnpg

pooled

with comparisonfor table from cesignifican of lelel reasonableany at rejected is

202/)13)(14(4

5.2853.289)0133.01(

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)564.15(106137270

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1)4(342

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106

1

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Page 71: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

71717171

Example 6.13: Plastic Film DataExample 6.13: Plastic Film Data

Page 72: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

72727272

Two-Way ANOVATwo-Way ANOVA

resintfacfaccor

g b

k

n

rkkr

g b

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2

1

2

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2

2

1111

Page 73: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

73737373

Effect of InteractionsEffect of Interactions

Page 74: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

74747474

Two-Way ANOVATwo-Way ANOVA

Page 75: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

75757575

Two-Way ANOVATwo-Way ANOVA

nintercatio 2factor -1factor

of effectsfor :)1(/SS

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2factor of effectsfor :)1(/SS

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fac

Page 76: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

76767676

Two-Way MANOVATwo-Way MANOVA

g b

k

n

rkkrkkr

g b

kkkkk

b

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g

g b

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n

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Page 77: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

77777777

Two-Way MANOVATwo-Way MANOVA

Page 78: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

78787878

Two-Way MANOVATwo-Way MANOVA

tioninterpretaclear

a havenot do effectsfactor theexist, effectsn interactio If

SSPSSP

SSP lambda sWilk'

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Page 79: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

79797979

Two-Way MANOVATwo-Way MANOVA

resfac

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pb

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SSPSSP

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if 0:reject samples, largeFor

effect 2factor for Test

SSPSSP

SSP lambda sWilk'

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)1)(1(1)1(

if 0:reject samples, largeFor

effect 1factor for Test

2

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Page 80: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

80808080

Bonferroni Confidence IntervalsBonferroni Confidence Intervals

res

qikiii

pqiki

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pimi

ngb

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E

Page 81: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

81818181

Example 6.13: MANOVA TableExample 6.13: MANOVA Table

Page 82: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

82828282

Example 6.13: InteractionExample 6.13: Interaction

rejectednot is n)interactio (no 0:

34.3)05.0(34.1

141)1(

31)1)(1(

:2/1)1)(1(

2/1)1(1

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222112110

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Page 83: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

83838383

Example 6.13: Effects of Example 6.13: Effects of Factors 1 & 2Factors 1 & 2

0:reject ,34.3)05.0(

0:reject ,34.3)05.0(

141)1(

311,26.42/

2/1

311,55.72/

2/1

5230.0SSPSSP

SSP

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SSP

21014,32

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11

2*2

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11

2*1

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Page 84: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

84848484

Profile AnalysisProfile AnalysisA battery of p treatments (tests, A battery of p treatments (tests, questions, etc.) are administered to questions, etc.) are administered to two or more group of subjectstwo or more group of subjectsThe question of equality of mean The question of equality of mean vectors is divided into several vectors is divided into several specific possibilitiesspecific possibilities– Are the profiles parallel?Are the profiles parallel?– Are the profiles coincident?Are the profiles coincident?– Are the profiles level?Are the profiles level?

Page 85: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

85858585

Example 6.14: Example 6.14: Love and Marriage Data Love and Marriage Data

Page 86: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

86868686

Population ProfilePopulation Profile

Page 87: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

87878787

Profile AnalysisProfile Analysis

pp

ii

iiii

H

piH

piH

222211121103

2102

12211101

:

level? profiles theAre

,,2,1,:

?coincident profiles theAre

,,3,2,:

parallel? profiles theAre

spopulation twoAssume

Page 88: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

88888888

Test for Parallel ProfilesTest for Parallel Profiles

)()1)(2(

'11

''

if levelat :Reject

)',(:),',(:

110000

000110

000011

21,121

212

221

1

2121

2

2101

212111

)1(

pnnp

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pjpj

pp

Fpnn

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cnn

T

H

CNN

xxCCCSCxx

CμCμ

CΣΣμCXCΣΣCμCX

C

Page 89: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

89898989

Test for Coincident ProfilesTest for Coincident Profiles

)()

2(

'11

'

''11

'

if levelat '':Reject

profiles parallelGiven

2,12

2

2

21

21

21

1

2121

2

2102

2121

nnnn

pooled

pooled

Ft

nn

nnT

H

1S1

xx1

xx11S1xx1

μ1μ1

Page 90: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

90909090

Test for Level ProfilesTest for Level Profiles

221

21

21

1

1,121

212

2121

03

)(1

)1)(1(

''')(

if levelat :Reject

profiles coincidentGiven

21

xxx

xCCSCCx

0Cμ

nn

n

nn

n

Fpnn

pnnc

cnn

H

pnnp

Page 91: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

91919191

Example 6.14Example 6.14

306.0029.0143.0161.0

029.0810.0173.0066.0

143.0173.0637.0262.0

161.0066.0262.0606.0

533.4

000.4

000.7

633.6

,

700.4

967.3

033.7

833.6

21

pooledS

xx

Page 92: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

92929292

Example 6.14: Example 6.14: Test for Parallel Profiles Test for Parallel Profiles

7.8)05.0(43030

)14)(23030(005.1

200.0

066.0

167.0

167.0

033.0

033.0

200.0

1100

0110

0011

100

110

011

001

1100

0110

0011

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21

FT

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Page 93: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

93939393

Example 6.14: Sample ProfilesExample 6.14: Sample Profiles

Page 94: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

94949494

Example 6.14: Example 6.14: Test for Coincident Profiles Test for Coincident Profiles

0.4)05.0(501.0

207.4301

301

367.0

207.4'

367.0'

58,1

2

2

21

FT

pooled1S1

xx1

Page 95: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

95959595

Example 6.15: Ulna Data, Example 6.15: Ulna Data, Control GroupControl Group

Page 96: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

96969696

Example 6.15: Ulna Data, Example 6.15: Ulna Data, Treatment GroupTreatment Group

Page 97: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

97979797

Comparison of Growth CurvesComparison of Growth Curves

X

ΣX

X

qqpp

q

q

qpqp

qq

qq

j

j

j

tt

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tt

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1

0

22

11

10

2210

1110

1

1

1

)(

modelRoy -Putthoff

covariance with normal teMultivaria:

,,2,1;,,2,1

groupin subject on tsmeasuremen ofvector :

Page 98: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

98989898

Comparison of Growth CurvesComparison of Growth Curves

)(ln2/)(

if adequate is polynomial that thehypothesis null Reject the

,'ˆˆ

)1)(/()1)((

')ˆ(Cov,

)11(1

''ˆ

: of estimators likelihood Maximum

2)1(

*

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1 1

11^

1

11

111

gqp

q

j

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pooled

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ggpooled

pooledpooled

gqpN

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n

knN

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WβBXβBXW

BSBβ

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XSBBSBβ

β

Page 99: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

99999999

Example 6.15Example 6.15

21.9)01.0(86.7ln2/)(

7627.0

8510941470 :GroupTreatment

0326430773 :Group Control

)27.0(8534.1)28.0(0274.2

)80.0(0900.4)83.0(6444.3

)50.2(1387.70)58.2(0701.73ˆˆ

modelgrowth quadratic Use

22)124(

*

*

2

2

21

gqpN

t.t..

t.t..

Page 100: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

100100100100

Example 6.16: Comparing Example 6.16: Comparing Multivariate and Univariate TestsMultivariate and Univariate Tests

Page 101: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

101101101101

Example 6.14: Comparing Example 6.14: Comparing Multivariate and Univariate TestsMultivariate and Univariate Tests

21

17,222

21

18,12

18,11

Reject

94.12)01.0(17

21829.17

: testsHotelling'

Accept

01.3)10.0(68.2:on test Univariate

01.3)10.0(46.2:on test Univariate

μμ

μμ

FcT

FFx

FFx

Page 102: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

102102102102

Strategy for Multivariate Strategy for Multivariate Comparison of TreatmentsComparison of Treatments

Try to identify outliersTry to identify outliers– Perform calculations with and without Perform calculations with and without

the outliersthe outliers

Perform a multivariate test of Perform a multivariate test of hypothesishypothesisCalculate the Bonferroni Calculate the Bonferroni simultaneous confidence intervalssimultaneous confidence intervals– For all pairs of groups or treatments, For all pairs of groups or treatments,

and all characteristicsand all characteristics

Page 103: 11 Comparison of Several Multivariate Means Shyh-Kang Jeng Department of Electrical Engineering/ Graduate Institute of Communication/ Graduate Institute

103103103103

Importance of Experimental DesignImportance of Experimental DesignDifferences could appear in only one Differences could appear in only one of the many characteristics or a few of the many characteristics or a few treatment combinationstreatment combinationsDifferences may become lost among Differences may become lost among all the inactive onesall the inactive onesBest preventative is a good Best preventative is a good experimental designexperimental design– Do not include too many other variables Do not include too many other variables

that are not expected to show that are not expected to show differencesdifferences