> In response to my question below, Russ wrote that data are generally
> globally scaled to a mean of 100 on the beta0 image I think (the
> baseline)? Is this true by default for spm2 data as I found several
> subjects with within-brain average beta0's in the 300's across all
> voxels?
I've observed this too. For an explanation see
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind0204&L=spm&P=R11588&I=-1
For more on how to robustly estimate typical intensity with the mode
see Appendix II in
Wen-Lin Luo and Thomas E. Nichols,
Diagnosis and exploration of massively univariate neuroimaging models.
NeuroImage, Volume 19, Issue 3, July 2003, Pages 1014-1032
-Tom
-- Thomas Nichols -------------------- Department of Biostatistics
http://www.sph.umich.edu/~nichols University of Michigan
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-------------------------------------- Ann Arbor, MI 48109-2029
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