Hey FSL users,
I want to check for a correlation between FA (which I derived from TBSS) and a percentage score. I have a group of 100 participants and I wonder if I did everything correctly since I got the following messages:
Critical Value for: Korrelation_Gruppenwahrsch-FA.nii.gz_clustere_corrp_tstat1 is: 0
Critical Value for: Korrelation_Gruppenwahrsch-FA.nii.gz_clusterm_corrp_tstat1 is: 0
Critical Value for: Korrelation_Gruppenwahrsch-FA.nii.gz_tfce_corrp_tstat1 is: 0
One-sample design detected; sign-flipping instead of permuting.
1.26765e+30 sign-flips required for exhaustive test of t-test 2
Doing 5000 random permutations
Starting permutation 1 (Unpermuted data)
Warning: The unpermuted statistic image for the current image contains no positive values, and cannot be processed with TFCE. A blank output image will be created.
Can you explain to me the error messages?
Demeaning the percentage scores is probably not right, is it?
I'd appreciate any help!
Vera
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