Dear Group
I have a basic question about global scaling and grand mean.
I searched archives and found similar questions asked without
clear answers to them.
Should I set 'Global scaling' option during the first level
analysis, if I plan to apply results to second level analysis
for group comparison later?
The scale of baseline from each subject are not same. Thus,
I am confused whether the first level analyses should have
the global scaling option or spm2 handles this matter by default.
Also, what is purpose of setting 'grand mean' to a specific value?
Thanks in advance,
Hyo Jong
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