I guess you would want to scale them to have same final PPheight if
you want to compare peak values via the PEs - that should be easy
using the info in the header of the design.mat file.
Cheers.
On 16 Mar 2009, at 18:24, Vishwadeep Ahluwalia wrote:
> Hi ,
> This is somewhat related to my previous question. I want to compare
> the same
> 16s/32s on/off block fMRI data with 3 different models. Model1:
> Block-On=16s
> , Model 2: Block-On=10s and Model3: Block-On=4s. Each convolved with
> Double
> gamma Hrf. I want to compare the PE values across these 3 models in
> different ROIs. The PP heights of these three models are different.
> Would i
> need to rescale each regressor to the same height?
> I would run 3 separate analysis on the same data, however is there a
> faster
> way i can do this?
> Thanks!
> -Vish
>
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