Thanks, Jesper, just a couple quick questions...
First of all, doing the second level comparisons -
>In the second you use the difference (subtraction image) between the two
>scans as your input-image, set up a two-sample t-test and the [1 1]
>contrast will give you the intevention effect and the [1 -1] and [-1 1]
>contrasts will give you the one-tailed interactions.
Did you mean [1 -1] in the two sample t-test to give group effects?
>You can of course still model unequal variances between groups, but to be
>honest I suspect it would make b**er all difference.
In the unlikely event that I would want to do the non-sphericity correction
to accomplish this, what would the replications be over? Subjects?
Allison Nugent
MRI Physicist
SNMAD/MIB/NIMH/NIH
Office: (301)451-8863
Mobile: (301)408-8560
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