During a multiple regression of PET data, estimation step, I repeatedly get the same error:
Temporal non-sphericity (over voxels)... REML estimation.
Warning: Matrix is singular to working precision.
In spm_remL at 87
spm_spm at 860
spm_spm at 299
??? Error using ==> svd
Nan or Inf prevents convergence
Error in ==> pinv @ 29
The error occurs even though the same PET scans work fine in a one sample t-test.
Any help pointing to the source of the error would be greatly appreciated.
Also, for the multiple regression (PET) option, why are they two different places to enough
covariates? What is the difference?
Thanks.
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