Dear FS experts, I want to add some in my early mail. If the contrast CM.C= [0 0 0 1] is designed for the interaction effect(time and group). How to design contrasts to do the main effect about the time and group? CM.C=[0 1 0 1] and CM.C=[0 0 1 1]? Or other? I wonder I may be wrong in designing matrix X in early mail. Please help me.Looking forward to reply, and thanks very much. Kind regards, Livia