Dear imagers,
I am running a FIR analysis a bit like Rik's example in the SPM manual. I am
using a full factorial model with one level for each time bin. I have also
included several conditions in the model. I have specified condition and
time bin as my two factors, and both are set as non-independent. Since this
gives me 98 cells, the non-sphericity correction is taking a long time. I
was wondering correction is actually necessary, at least between time bins,
since correlations between time bins should have been accounted for by AR(1)
correction in the FFX. What would you advise?
Many thanks,
Paul Wright
--
Paul Wright PhD
Centre for Speech, Language, and the Brain
Dept. of Experimental Psychology Tel: +44 (0)1223 766559
University of Cambridge Fax: +44 (0)1223 766452
Downing Street email:[log in to unmask]
Cambridge http://csl.psychol.cam.ac.uk
CB3 2EB
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