Dear Jeanette
I am doing a MRI VBM analysis.
(1) I think you meant that I should demean the scores of ALL subjects( patients and controls ) together and then enter them separately into 2 different EVs.
(2) I have a quite simple question about the demeaning......Often, the mean value is not an integer, and after subtraction of the mean the sum of the new "demeaned" values is not zero....for example, the sum might be 0.1, and I have 60 subjects. So what should I do about that? should I randomly pick up a subject and subtract 0.1? or should I subtract 0.1/60 from all subjects ( but that's not an integer as well)?
Thanks a lot!
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