Dear fsl experts,
I'm new to design matrix of repeated measures and Anovas and would really appreciate your help. I read the posts in the forum but I'm still not sure if my design and t and f contrasts are correct.
My experiment is comprised of 3 groups (between subjects), and each group has 2 time points (within effect).
the design matrix:
group column 1:3 (separating the groups?), ev1 - first group difference (1 for first scans -1 for the second scans) ev2 2nd group difference, 3rd group difference, and then ev for each subjects mean.
contrast:
does the contrast [ 1 -1 -1] tests if the first group has greater increase( from scan 1 to scan 2) than both other groups? Will [ -1 1 1] tests if the first group has greater decrease than both other groups?
1 0 0 … tests if the first group scans of the first time is greater than the second time?
-1 0 0 tests for the opposite direction of change in the first group (decrease from first to second scan)?
Can I set these contrasts for each group?
one F test:
1 1 0 0 0 0 0 0 0 0 – main effect for time?
Thanks!!
Len
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