Hi Jeanette,
I wasn't expecting a perfect match, and not even a perfect match between 2*p(Ttest) and p(Ftest). I just wasn't expecting as big a difference as I got (see summary measures below). Especially the corrected p values differ no end: minima of 1(?!) versus 0.07. With respect to raw p-values, the robust minumum raw p in the Ftest is more than 70 times higher than the Ttest's.
Although the F fits T² perfectly in every voxel, the TFCE Tstats are higher than the TFCE Fstats. I was just wondering if this has something to do with the bi-directional quality of F statistics: could it make the data less spatially consistent? And secondly, could an Ftest lead to larger clusters in permutations / by chance?
Many thanks for your help,
Emma
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SUMMARY MEASURES:
Corrp: fslstats -R
Ftest: 0.000000 to 0.000000
Ttest:. 0.000000 to 0.923800
Corrp: fslstats -r
Ftest: 0.000000 to 0.000000
Ttest: 0.019400 to 0.897010
Raw p: fslstats -R
Ftest: 0.000000 to 0.991200
Ttest: 0.000000 to 0.998600
Raw p: fslstats -r
Ftest: 0.098129 0.363770
Ttest: 0.567205 0.991610
TFCE: fslstats -R
Ftest: 0.000000 160431.156250
Ttest: 0.000000 183206.484375
TFCE: fslstats -r
Ftest: 3850.347656 56792.628906
Ttest: 366.412964 153343.828125
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