Dear FSL experts,
I'm quite new to statistical inference so maybe I'm asking a silly question but I didn't manage to find an answer in the FslWiki :(
My dataset has 120 subjects' FA maps, divided into three groups, healthy controls, mci, alzheimers. I runned a F-test with three groups using design same as http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/GLM. I got a tbss_tfce_corrp_fstats1.nii.gz and three tbss_tfce_corrp_tstats1/2/3.
First, I guess that the F-stat image tells me if (and in which voxels) there's a significant difference between the three groups, is it correct?
Second, what is the meaning of the three t-stats images? (Previously I did some two-groups tests and I know that tstat1 tells me where FA is higher in the first group than in the second, tstat2 viceversa; how is this generalized to the case of three groups?)
Thank you so much.
Marzia