I'm not quite sure what you are asking. Contrast 1 and contrast2 both
compare condition1 and condition2. The results are simply inverted.
Contrasts always contain positive and negatives, however, SPM only
displays positives. You really only need to test 1 of your contrasts
at the group level.
Best Regards, Donald McLaren
=================
D.G. McLaren, Ph.D.
Research Fellow, Department of Neurology, Massachusetts General Hospital and
Harvard Medical School
Postdoctoral Research Fellow, GRECC, Bedford VA
Website: http://www.martinos.org/~mclaren
Office: (773) 406-2464
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On Wed, Jan 23, 2013 at 4:12 PM, Christian <[log in to unmask]> wrote:
> Hi Donald,
>
> thank you very much for your answer! Okay, that's why the results are identical... I got it.
>
> But does this also means that the two sample t-test is the wrong design to compare contrast1 and contrast2 with focus on both patients controls? What would be a better analytic strategy?
>
> Thanks and best regards,
> Christian
>
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