Hi Markus,
> i checked all my cells, no mistakes in there. i found the problem (but no
> solution): i defined a nuisance covariate, which i forgot to mention
> before. deleting the covariate let spm design the model. but how can i
> intergrate a covariate? i tried interaction with factor 1 (i don't
> understand why i can choose 3 factors and defined only 2) but it still not
> worked.
It sounds like you might be trying to treat the covariate as a factor.
There is a separate "Covariates" tab below "Design" (in which
full-factorial is specified), which lets you add a covariate.
My understanding of your setup is that you want two factors, entering
the cells as you outlined, and then add a separate covariate. Unless
you specifically want something different, I would guess that you
probably don't want any interactions of this covariate with your factors.
I hope I haven't misunderstood the problem...
Ged.
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