Many thanks to those of you who replied (both offlist and on). Several of you
suggested checking that the # of scans specified in the model versus the # of
scans selected. Though that would certainly cause problems it was not the case
here.
A search in the archives for "spdiags error" produces the following (among
others), which ultimately solved it:
http://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind05&L=SPM&P=R514650&I=-3&X=39211A7A01151E95BB&Y
It was actually a result of the SPM2 software not being able to perform
non-sphericity correction appropriately for our design as it was set up.
Not wanting to either increase the number of images or decrease complexity of
the design, we chose to estimate the model without serial autocorrelations.
Carolyn
Carolyn L. Fort
Research Specialist, Senior
Department of Psychiatry
University of Arizona
PO Box 245002
Tucson, AZ 85724-5002
v: 520-626-8568
f: 520-626-6050
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