Hi - if you want a 'mixed' design in this way I presume that the best
solution is just to change the setup contrasts option from "Original
EVs" to "Real EVs" and hand-setup the contrasts for every single basis-
set EV?
Cheers.
On 20 May 2009, at 19:33, Greg Burgess wrote:
> Hello FSL listers,
>
> I'm trying to run a lower-level state-item analysis. In these
> analyses, you include both
> blocked and event-related regressors simultaneously in your model.
> One constraint is that
> your event-related regressors need to be modeled with an FIR basis
> set and your blocked
> regressors need to be modeled with an assumed response shape such as
> the double-
> gamma (c.f. Visscher et al. 2003 for the rationale behind these
> constraints). The
> contrasts will compare the event-related EVs to other event-related
> EVs, and the blocked
> EVs to other blocked EVs.
>
> However, when I try to set up the EVs in the full model setup, I get
> the following error: In
> order to setup contrasts in "Original EVs" mode whilst using basis
> functions or sinusoidal
> harmonics, all the original EVs must be the same basic shape and
> generate the same
> number of real EVs. Please change the EV setup.
>
> If I attempt to create the model using Real EVs, the GUI becomes
> quickly overwhelmed
> (i.e., unusable / freezes) trying to create a matrix of (9 event-
> related EVs x 9 FIRs) +
> three blocked EVs. Even if it didn't freeze, it's just a pain to set
> up that many contrasts
> rather than just using Original EVs.
>
> Is there a way to force feat_gui to allow me to use different basis
> functions for the
> different EVs, as long as I contrast only EVs that have the same
> basis functions?
> Otherwise, is there a relatively easy way to combine two separate
> design.fsf's into one
> design.fsf that will solve for the blocked and event-related Evs
> simultaneously?
>
> Thanks,
> --Greg
>
> ____________________________________________________________________
> Greg Burgess, Ph.D.
> Research Associate, Institute of Cognitive Science
> University of Colorado - Boulder
> Email: [log in to unmask]
>
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