Hi,
On 3 Mar 2009, at 02:14, shih-Wei Wu wrote:
> Dear all,
>
> I have 2 quick questions about demeaning:
> 1. Does 'demeaning' take the mean of the regressor time series and
> subtract
> it from the time series?
Yes.
> Or does it take the mean of the regressor values,
> and subtract it from the time points where regressor values are
> specified?
>
> 2. Does demean take place before convolution with HRF or after?
> Would this
> make a difference?
It depends on the exact options chosen, but generally both.
Cheers.
>
> thanks
> shihwei
>
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Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
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