Dear SPM experts,
I am currently experiencing a quite strange behavior in a 2-group t-test
("Basic models", VBM analysis) design with SPM8 comparing a single subject to
a group with default settings.
The design matrix also looks fine after setup (no grey fields in the "beta
not uniquely specified" row). However after estimation in some cases (about
1/3) the first column has an empty beta image (beta_0001) and the "beta not
uniquely specified" field is now grey (see attached images). Unsurprisingly
no contrast can be specified and all kinds of error messages are given when I
try regardless... I am a bit puzzled why this is happening, again it only is
in approx. 1/3 of cases. The other 2/3 of cases work as expected.
Any suggestions are very much welcome.
Niels
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Dr. med. Niels Focke
Dept. of Clin. Neurophysiology
UMG - University Hospital Göttingen
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