SPM Experts,
I am performing a multiple regression analysis (VBM) and I was wondering if the mean is always modeled in the design matrix? I have 3 covariates that I have entered (1 of interest and 2 nuisance), yet when I load the design, the matrix adds a 4th mean column. How might this mean column impact the results?
Also, I was wondering what the advantage was of using an Absolute Masking Threshold at 0.1? Would it be more advantageous to run 'None' (for the Masking) in combination with an Explicit GM tmp?
Cheers!
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