Hi Anda,
I suspect the problem is the explicit modeling of the baseline. That will
make the design rank deficient (singular, in this case) and create
problems. Why not model the baseline implicitly (ie don't put it in the
model)?
Joe
Joseph Devlin, Ph. D.
FMRIB, Dept. of Clinical Neurology
University of Oxford
John Radcliffe Hospital
Headley Way, Headington
Oxford OX3 9DU, U.K.
Phone: +44 (0)1865 222 494
Fax: +44 (0)1865 222 717
Email: [log in to unmask]
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