I recently set up a longitudinal model and processing through the VBM8 toolbox, but the matrix model came out a bit reversed than what I’m used to seeing (i.e., subjects first, then group, etc.). I’ve attached a picture of the model. Is this a problem?
The first columns are group (1,2), the time (3,4,5,), the group x time for each group (6,7,8; 9,10,11), then followed by each subject.
What contrasts should be used in this “reversed” model matrix for comparison of group x time interaction and the main effects?
Thanks for any help.
Regards to all,
Jeff
