Dear all
I have two questions for you. Would you like to give me some suffestion. Thanks.
1. I have three groups (group A,group B and group C). I'm not sure how to do F test. Should I choose the item " Any difference between (gA gB gC) in the 'Between-subject contrast'"? If it shows significant difference after F test, then should I do 3 times of T_test between group A and B, between group A and C and between B and C?
2. I am really confused about interaction analysis. Now I want to do the interaction effects of two gene polymorphisms on the network connectivity. In gene 1 , there are 3 levles. And in gene 2, there are 2 levels. So in the 'Subject effects' box, there are 5 groups:
gene 1_level 1;
gene 1_level 2;
gene 1_level 3;
gene 2_level 1;
gene 2_level2;
So what is the contrast matrix in the 3 x 2 interaction analysis？ Moreover，if there is significant interaction effect, then how to do the post hoc analysis?
I'm sorry for disturbing you with so many questions.
I hope it won't take you too much time. Thank you very much.
Best wishes.

yours 
lin