Hi - yes this is important otherwise you can't easily interpret
contrasts between conditions. The normal way is just to make sure that
the EVs are of height 1 as input to FEAT, i.e. before convolution,
etc., and then this is all comparable across EVs.
Cheers.
On 9 Dec 2008, at 01:42, shih-Wei Wu wrote:
> Dear all,
>
> A question with regard to scaling of parametric regressors.
>
> I have 3 parametric regressors that occupy different time points
> during a trial. The range of
> values between the regressors differ. One regressor has range
> approx. [-1,1] with mean at
> 0, the second regressor has range [-3,3], and the third regressor
> [-5,5].
>
> What would be the correct way to re-scale them so I don't have to
> worry about scaling
> problems when running the GLM?
>
> thanks!
> shihwei
>
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