Dear SPM-experts,
I would like to compare correlations in both independent and paired samples.
Previously, I was able to calculate a comparison of regression slopes
beta...
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind1201&L=SPM&P=R34291&I=-3&d=No+Match%3BMatch%3BMatches
... but I am also interested in comparing correlation coefficients r.
On a voxel-wise basis, this can be implemented in Matlab, e.g. for
paired samples using a z-statistik given in Steiger, Psychological
Bulletin 87(2): 245-251, 1980.
However, the problem is to apply corrections for multiple comparisons in
the SPM framework (random field theory).
Is it possible to either...
1) ...load the resulting z-maps and apply correctionns? If yes, how can
I do that (by providing a mask, df, etc)?
2) ...or implement the comparison of correlations directly in SPM?
Thank you for your help and kind regards,
Andreas.
--
Andreas Hahn, MSc.
Functional, Molecular & Translational Neuroimaging
Department of Psychiatry and Psychotherapy
Medical University of Vienna, Austria
Phone: +43 664 8001662002
Email: [log in to unmask]
Web: http://www.meduniwien.ac.at/neuroimaging/
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