>Dear Thomas,
>
>> We are analyzing PET data of subjects from 2 groups who underwent the
>> same stimulation. Group1 contains 7 subjects, Group2 contains 12
>> subjects. We can do a single subject analysis and a RFX group
>> evaluation of group 2. For the group evaluation of group 1 the number of
>> 7 subjects might be not enough. (?) We want to do a comparison of the 2
>> groups. Which model do we have to use for the first and second level
>> analysis?
>
>For the 1st-level analysis use a 'multi-group conditions and covariates'
>for the 2nd-level analysis compare the two sets of subject-specific
>contrasts with a two sample t test under 'basic models'. The latter will
>have reasonable power because you are using all 19 subjects.
>
>I hope this helps - Karl
Dear Karl,
when we do a 'multi-group conditions and covariates' analysis, we can
not produce the subject specific contrast images, because the columns
of the design matrix contain the different conditions for all subjects.
How can we obtain the contrast images to enter into the second level
analysis ?
Do we have to use the results from the single subject analysis ?
Thank you
Thomas Stephan
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Thomas Stephan Email: [log in to unmask]
Klinikum Grosshadern
Neurologisches Forschungshaus
Marchioninistr. 23 Fon: +49 089 / 7095-4819 *NEU*
81377 Muenchen Fax: +49 089 / 7095-4801
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