Richard Blanch,
Hello. I have written code to implement the paper: "Mapping
Voxel-Based Statistical Power on Parametric Images" by JD Van Horn et al.
Neuroimage 7, 97-107 (1998). This may be of interest and use to you. You
can find it at:
http://web.njit.edu/~jrs3/matlabfiles/
Jason.
On Tue, 3 Dec 2002, Richard Blanch wrote:
> Hi
>
> We are having problems attempting to do a power calculation for fMRI.
>
> I know that power calculations for SPM are particularly difficult; however, we need to do one because we got a negative result and would like to attach a p value to the likelihood of there being a population difference and us not finding it.
>
> The set up we have is two groups of subjects (one of 12 and one of 13) that we are comparing using a 2-sample t-test.
>
> How can we go about doing a retrospective power calculation for this experiment?
>
> Any help would be much appreciated!
>
> Richard Blanch
>
>
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Jason Steffener, RTS V
Department of Psychiatry
New Jersey Medical School
Newark, NJ USA
(973) 972-1604
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