Hello Gwenaelle,
Thank you for your response, it is very re-assuring.
With regards to the error messages you said:
>It is probably because you've run exactly the model above that is
>indeed rank deficient. You just need to add some subjects (and
>presumably you've got more than one control) as some additional EVs and
>it should not be a problem anymore...
Actually, I have run this model in Glm using 24 controls, 15 abstinent
subjects, and 5 relapsers. That is when the error message appears. So,
adding the EVs in the same way I did with the example dataset does not
seem to resolve this error message. Do you have other thoughts about
why this could be happening?
Thank you so much.
Omar
> Problem with processing the model. Warning: at least one EV is (close
> to) a linear combination of the others. You probably need to alter
> your design. (Design matrix is rank deficient - ratio of min:max
> eigenvalues in SVD of matrix is 1.21792e-17).
>
> Warning-design matrix uses different groups (for different variances),
> but these do not contain "separable" Evs for the different groups (it
> is necessary that, for each EV, only one of the groups has non-zero
> values).
Hope this helps,
Gwenaelle
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