Re: Box's test warning

Posted by David Marso on Jun 13, 2013; 8:36pm
URL: http://spssx-discussion.165.s1.nabble.com/Box-s-test-warning-tp5720700p5720705.html

Hammering away with the following indicates that both are npd!
Also several HUGE correlations!
You did not answer the critical question!!!
SAMPLE SIZE for each group???
data list list / v1 to v6.
begin data
44.389 22.886 21.503 25.124 15.228 16.916
22.886 19.302 3.584 11.095 7.594 8.462
21.503 3.584 17.919 14.029 7.635 8.454
25.124 11.095 14.029 19.374 9.533 9.521
15.228 7.594 7.635 9.533 9.892 5.853
16.916 8.462 8.454 9.521 5.853 13.457
55.915 26.646 29.269 38.409 13.996 26.429
26.646 21.635 5.011 16.137 9.195 11.583
29.269 5.011 24.258 22.271 4.801 14.846
38.409 16.137 22.271 34.081 8.639 19.834
13.996 9.195 4.801 8.639 9.501 5.089
26.429 11.583 14.846 19.834 5.089 20.452
end data.
compute gp=$CASENUM GT 6.
LIST.
MATRIX.
GET COV01 / FILE * / VAR v1 to v6.
COMPUTE C1=COV01(1:6,:).
PRINT C1.
COMPUTE C2=COV01(7:12,:).
PRINT C2.
COMPUTE Inv1=GINV(C1).
COMPUTE Inv2=GINV(C2).
PRINT Inv1.
PRINT Inv2.
CALL EIGEN(C1,EVec1,EValue1).
PRINT EVec1.
PRINT EValue1.
CALL EIGEN(C2,EVec2,EValue2).
PRINT EVec2.
PRINT EValue2.

COMPUTE D1I=INV( SQRT( MDIAG(DIAG(C1)))).
PRINT D1I.
COMPUTE R1=D1I * C1 * D1I.
PRINT R1.
COMPUTE D2I=INV( SQRT( MDIAG(DIAG(C2)))).
PRINT D2I.
COMPUTE R2=D2I * C2 * D2I.
PRINT R2.

END MATRIX.

The Burl wrote

Yep. Sure do have an adviser. Most people working on dissertations do...

Here's the covariance matrix between my two groups after I split the file by my two groups. Hope this helps.

covariances.pdf