Hi,
you have to setup this contrast on the first level. If your four conditions A, B, C, D are represented by a vector (1 1 1 1), then the contrasts are as follows:
A>B -> (1 -1 0 0)
C>D -> (0 0 1 -1)
(A>B) > (C>D) -> (1 -1 -1 1)
Hope that helps,
Cornelius
Am 27.04.2011 um 18:13 schrieb Lara Foland-Ross:
> Dear FSLers,
>
> I have a basic question, the answer for which I couldn't find anywhere on the email list or fsl website. My apologies if I missed the solution to my problem...
>
> I have a simple task design with 4 conditions: A, B, C, D. I first contrasted A>B and C>D, and would now like to contrast (A>B)>(C>D). How does one accomplish this within feat?
>
> Many thanks,
> Lara
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