Hello SPM-users,
while defining a t-contrast in an ANCOVA model from the basic models menu
(VBM) having two groups and one nuisance variable, SPM2 does not accept the
contrast vector
-1 1 0 0
(third column is empty in the design, fourth column is the nuisance variable)
but SPM2 notes 'no valid contrast defined'. The same with the opposite
contrast 1 -1 0 0.
Writing permissions etc. have been checked, this seems alright.
Only the standard effects of interest F-contrast can be submitted and
displayed.
Is this some bug in the contrast parser? (Matlab 7 is used). SPM2 has been
downloaded only recently.
Thanks a lot in advance,
Philipp
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