Sorry that i didn't clarify my question.
the following is the original question asked by Dr. John Colby
>What I am confused about is this: When age is included as a covariate (as
>opposed to when it is not), the individual FA_tfce_corrp_tstat maps are more
>robust, but the overall F-test map (FA_tfce_corrp_fstat) drops almost to
>zero. This opposite behavior surprised me and makes me think that I might be
>doing something wrong in my model setup, or perhaps just not fully
>understanding how F-tests work in FSL. Does this seem like normal behavior,
>or does it look like I'm doing something wrong?
we also met the same question like above.
the f-test result seems a lil bit different with the t-test result from each t-contrast.
the f-values were small, and we can barely detect any significant difference from f-test in TFCE (while p<0.05).
i think it is not a normal result.
cuz the f-test findings should not be so different from t-test, since we got many significant findings from t-test analysis.
there must be something wrong with my F-test setting, or i must misunderstanding the meaning of F-test in FSL...
Any help would be so appreciated!!!
thanks
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