Hi,
I want to carry out a conjunction analysis on the results of randomise,
and apply tfce to the results.
To do so, I ran randomise, converted the uncorrected p maps to z maps,
and took the minimum from both compared maps. I fed this minimum
statistics map into fslmaths with the -tfce option.
So, now my maybe a bit naive questions: How can I convert the resulting
tfce-map into a map of p- or z-values? In the paper from 2009 it was
stated: "For inference, the TFCE image can easily be turned into
voxel-wise p-values (either uncorrected, or corrected for multiple
comparisons across space) via permutation testing.", but somehow I am
missing the clue how to implement this.
I also want to obtain the corrdected p stats, that I would get when
using the tfce option within randomise, is there an easy way to process
the output from fslmaths in order to get such maps? I would be happy
about any pointer.
Btw, is it a bug or an intended feature, that randomise produces an
thresholded output for the t statistics if no mask is specified, but
when for example a brain map is provided, I would get the complete
t-statisticcs, including negative values?
Thanks for any suggestions,
wolf
|