Do I include that as a separate EV or as a voxel dependant EV?
--
Andres Roman
> From: Michael Harms <[log in to unmask]>
> Reply-To: FSL - FMRIB's Software Library <[log in to unmask]>
> Date: Wed, 16 Feb 2011 09:28:03 -0600
> To: <[log in to unmask]>
> Subject: Re: [FSL] Adding covariates in a multisession-multisubjection model
>
> Hi Andres,
>
> If I understand you correctly, your 2nd level is just combining across
> runs of the same subject. In that case, handedness doesn't change
> across run (same as gender), so you would not include handedness in the
> 2nd level. You could include both in a 3rd level analysis (across
> subjects) however.
>
> Best,
> -MH
>
> On Tue, 2011-02-15 at 17:20 +0000, Andres Roman wrote:
>> Hi All,a
>> I am doing the group analysis for a task that has 36 trials divided in two
>> runs. I was wondering about the use of covariates (sex and handedness) in
>> feat when you have such a model. I think that since I am doing a
>> multisession multisubject analysis I should add them as independent EV's in
>> the third level analysis after I merged my two runs in the second level
>> analysis using a fixed effect model. I figured that's the right way to
>> covariate for gender but im not so sure about handedness since that might
>> affect my second level analysis. Do you have any tips or hints for this?
>> Thank you very much
>>
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