Catalina,
Here's an answer to one of your questions:
> The second questions is about the number of resels within the search volume:
> For example S=2384753mm^3=162503 voxels, 1 resel=47.17 voxels but S=3229
> resels not 3445 that are expected. Why is this difference? How do you
> compute the number of the voxels within aresel and the number of the resels
> within the search volume? If I divide S by the product of the FWHM_i i get
> 3485 resels in S thus another value.
See the end of this message for answer:
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind0103&L=spm&P=R1537
In short, the RESEL calculation uses a slightly different measure of
volume which comes out slightly smaller than S. This slight
difference makes the RESEL count more accurate (for the purpose of
generating random field theory corrected p-values).
-Tom
-- Thomas Nichols -------------------- Department of Biostatistics
http://www.sph.umich.edu/~nichols University of Michigan
[log in to unmask] 1420 Washington Heights
-------------------------------------- Ann Arbor, MI 48109-2029
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