Hello-
The FDR web page recommends inverting the vox_tstat results of randomise
before obtaining a threshold value. I'm wondering why simply inverting
the desired alpha value wouldn't (and doesn't) return the same results.
For example, instead of the recommended:
avwmaths grot_vox_tstat1 -mul -1 -add 1 1_minus_grot_vox_tstat1
fdr -i 1_minus_grot_vox_tstat1 -m mask -q 0.05
avwmaths grot_vox_tstat1 -thr <1 - FDR threshold>
thresh_grot_vox_tstat1
why not simply run:
fdr -i grot_vox_tstat1 -m mask -q 0.95
avwmaths grot_vox_tstat1 -thr <FDR threshold> thresh_grot_vox_tstat1
I can see that the results are different when I run these commands on my
data, but is there a clear explanation as to why?
Thanks much,
--
Jim Porter
TRiCAM Lab Coordinator
Elliott Hall N437
612.624.3892
www.psych.umn.edu/research/tricam
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