Hi - if you are entering each group's covariates in a separate EV
then each set of values should be demeaned separately before padding
with zeros (the zeros corresponding to the other group).
Cheers.
On 3 Oct 2007, at 02:49, Gabriel S. Dichter, PhD wrote:
> Dear FSL users
>
> We would like to include a symptom measure as a covariate in a 2-
> group design. When we enter this variable as an EV, is the mean-
> centering of this variable done across both groups, or within each
> group separately?
>
> Thank you for your help
>
> Gabriel Dichter
> Department of Psychiatry
> University of North Carolina at Chapel Hill
> Chapel Hill, NC
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