Where, Grp is the group variable, G's are the groups and s is for the subject variables. The negative numbers in the group column give T1 and non-negative give T2.
Contrasts:
G1 G2 G3 s1 s2 s3 s4 s5 s6
1 0 0 0 0 0 0 0 0 Time2 > Time1 G1
0 1 0 0 0 0 0 0 0 Time2 > Time1 G2
0 0 1 0 0 0 0 0 0 Time2 > Time1 G3
-1 1 0 0 0 0 0 0 0 G2>G1
-1 0 1 0 0 0 0 0 0 G3>G1
1 -1 0 0 0 0 0 0 0 G1>G2
0 -1 1 0 0 0 0 0 0 G3>G2
1 0 -1 0 0 0 0 0 0 G1>G3
0 1 -1 0 0 0 0 0 0 G2>G3
Is this correct?
Also, is this only possible in a balanced design where there are equal number of people at both time points?
Thanks,
Tom