It looks like you are using a lower case ( -f ) for the
F-test cluster threshold option, this should be a
capital F ( e.g. -F 2.3 ) - can you try this and let us
know if the error changes?
> Dear FSLers,
> I am new to FSL and am currently analysing 4 groups DTI TBSS data and have
> worked my way through the tutorial and posts on the mailing list. However,
> I am still confused with the F-Test.
> If I include the -f design.fts option but not specify an -F [number]
> option, I get an error message that no specific option was selected but if
> I do say -F 1 then I get another error message. So concretely, I had used
> the example on the TBSS stats webpage:
> randomise -i all_FA_skeletonised -o tbss -m mean_FA_skeleton_mask -d
> model_test1.mat -t model_test1.con -f model_test1.fts -n 5000 -c 2 -V
> Loading Data:
> Data loaded
> 1.16979e+44 permutations required for exhaustive test of f-test 1
> Doing 5000 random permutations
> Warning! No output options selected. Outputing raw tstat only
> I had then tried
> randomise options: -i all_FA_skeletonised -o tbss -m mean_FA_skeleton_mask
> -d model_test1.mat -t model_test1.con -f model_test1.fts -n 5000 -c 2 -f 1
> but got
> Loading Data: ERROR: Program failed
> An exception has been thrown
> Unable to open 1
> If my design matrix is such that
> 1 -1 0 0 check
> 1 0 -1 0 check
> 1 0 0 -1 check
> …… set of remaining t-contrasts here without selection of F, e.g.,
> 0 0 1 -1 not checked
> … etc
> What option should I use in randomize to get the output for my F-test?
> Should I use a combination of these to specify the contrast or can I
> ignore the error and check this once the statistics have run?
> Many thanks in advance for any suggestions!