Dear Ben,
A > (B-C) can be rearranged (by adding C to both sides of the inequality)
to give (A+C) > B.
The contrast you would need is:
A B C
1 -1 1
Are you sure that this is what you really want? It seems like a very odd
contrast to me, but of course I don't know the context.
Good luck!
Richard.
At 14:40 30/10/2001 -0500, you wrote:
>Dear spm folks,
> If I have a block design fMRI study with three conditions: A, B, and
>C, how do I set a contrast that would allow me to see A > (B-C) for each
>subject?
> Many thanks.
>Ben
>-----------------------------------
>Benjamin Xu, Ph.D.
>ERB/CNS, NINDS
>National Institutes of Health
>5N250 Building 10
>Bethesda, MD 20892
>U.S.A.
>Phone: 301-435-8542
Dr Richard Perry, Clinical Lecturer,
Wellcome Department of Cognitive Neurology,
University College London, Gower Street, LONDON WC1E 6BT
Tel: (020) 7679 2187 Fax: (020) 7679 7316
E mail: [log in to unmask]
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