Dear SPM users,
When I was performing a multiple correction analysis, I encountered
several issues and questions:
1) I’m trying to figure out whether the information stored in xVol.FWHM
actually corresponds to the smoothness of the residuals. I read
somewhere that xVol.FWHM corresponds to the smoothness of the
components, but are those components the residuals? Or what does
xVol.FWHM reflect?
2) In any case, I believe that the smoothness is defined in voxels and
I will need to convert them in mm, could you suggest me a way of doing
so?
3) Finally, I’m also dealing with the issue of whether one should base
the smoothness estimation on individual models rather than group tests.
This point is pretty important for the correction analysis.
Thank you very much in advance!
Maryem Torres-Quesada
PhD
University of Granada
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