Hello SPM,
in a VBM analysis we compared the hemispheres of a group of subjects,
first with a two sample t-test, then additional with a paired t-test.
The results look somehow strange when using the paired t-test.
The results table tells me that the calculated smoothness of the results
both analyses are completely different:
two-sample t-test: smoothness FWHM = 8.2 8.6 8.0 mm
paired t-test: smoothness FWHM = 0.0 2.6 2.4 mm
Why is that?
Andreas
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