Hi,
On 11 Nov 2008, at 13:38, Dan Wolf wrote:
> Hello,
> Do the columns corresponding to EVs in the design.mat file reflect
> the shape of the effective
> EV after orthogonalizing wrt to motion parameters (when that option
> is selected)?
No, and in fact the main EVs are NOT orthogonalised wrt the motion
regressors. Where the bubble-help/manual talks about "only the
orthogonal component of the main EVs" is used, it is referring to the
fact that it is always the case that only the orthogonal component
drives the statistics on the EVs of interest, even without
orthogonalising them - that's the way the GLM works, even though you
haven't explicitly orthogonalised the main EVs.
Cheers.
> Or is the
> orthogonalization done during subsequent steps? If its done in
> subsequent steps, is there a
> way to see the shape of the post-orthogonalization EVs?
>
> Thanks,
> Dan
>
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Stephen M. Smith, Professor of Biomedical Engineering
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FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
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