Hi - at second level, with the FE option, you do not need to include
one EV per run, as the FE modelling is not trying to model the cross-
run variance anyway, it is just pooling across the first-level
variances (that's the definition of a FE model). So if you do this
(i.e., following the example from the FEAT manual) all should work ok.
Cheers.
On 13 Oct 2008, at 21:43, Michael W. Cole wrote:
> Hello,
>
> I'm using FEAT to run a 3-level analysis. My study has 10 runs per
> subject with 15 subjects. The second level combines runs (using
> fixed-effects) and the third level combines subjects (using mixed-
> effects). I included a separate EV for each run at the second level
> to remove inter-run mean effects (making it repeated-measures). I
> tried doing this (one EV per subject) at the 3rd level, using FLAME,
> and I get this error: "Singular design. Number of EVs > number of
> time points." and the script crashes. It works, however, if I
> perform a fixed-effects analysis instead of using FLAME.
>
> Is there a better way to account for run and subject differences in
> these models? Why would this work with fixed-effects but not FLAME?
>
> Thank you,
> Michael
>
>
> --
> Michael W. Cole
> Ph.D. candidate, Center for Neuroscience
> University of Pittsburgh
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