Dear Torben,
thanks for your reply!
The effect of interest looked ok in sense that only relevant column were
marked as "of interest" above my design matrix.
Eventually, in order to put my mind in peace, I performed two
single-subject analyses, explicitly specifying only SPM.xX.iG in the
first one, and both SPM.xX.iG and SPM.xX.iC in the second one.
Both analyses included realignment parameters and AR(1) correction.
I found no difference between results of those two analyses when looking
at the result tables as provided by F(effect of interest) and some
T-contrasts.
So, it looks for me like it is rather SPM.xX.iG than SPM.xX.iC that
finally influences what is "of interest".
At least in my particular case specifying SPM.xX.iC happen to be redundant.
It makes me happy since I do not need to re-process my data :)
Best regards,
Victor
> Most likely yes. You can check it yourself by selecting the effects of
> interest in the results section.
>
>
> best
> torben
>
>
> Victor Vorobyev wrote:
>
>> Dear SPM users,
>>
>> could anyone tell me how the effect of interest is defined in SPM2:
>> is it the one specified by SPM.xX.iC, or is it everything that is NOT
>> specified by SPM.xX.iB and SPM.xX.iG ?
>>
>> The reason I am asking is that I used batch mode to process my group
>> fMRI data as a fixed-effect model with realignment parameters included
>> as regressors of no interest. Therefore I specified SPM.xX.iG to mark
>> the effect of no interest, but somehow forgot to change SPM.xX.iC (that
>> now contain all columns including those specified in SPM.xX.iG).
>>
>> Unfortunately I noticed that my mistake only after I had completed all
>> the long-lasting computations, so I am wondering did I make a critical
>> mistake or not? Specifically, did it lead to wrong AR(1) estimation?
>>
>> thank you!
>>
>> Victor
>>
>>
>> *********************************
>> Victor Vorobyev, Ph.D.
>> Centre for Cognitive Neuroscience
>> University of Turku
>> Finland
>> *********************************
>
>
--
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Centre for Cognitive Neuroscience
Department of Psychology
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