Dear Donald
Thank you very much for your kind reply.
So when I perform ANCOVA among three groups (saying A,B and C) with age and gender as nuisance covariates,
am I correct in creating F-value contrast matrix as follows?
A B C age gender
1 -1 0 0 0
0 1 -1 0 0
0 0 0 0 0
Then when I perform pairwise post hoc t-test , am I correct in creating respective T-value contrast matrix as follows?
1 -1 0 0 0 A>B
-1 1 0 0 0 A<B
0 1 -1 0 0 B>C
0 -1 1 0 0 B<C
1 0 -1 0 0 A>C
-1 0 1 0 0 A<C
Fuerthermore if the significantly different regions identified with the post hoc t-test are larger than those with ANCOVA,
how should I interpret those regions outside of those found with ANCOVA?
Thank you very much for your kind help.
Takuya
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