Dear Johannes,
A mixed 2x3x2 factorial design is covered explicitly in these two documents:
https://en.wikibooks.org/wiki/SPM/Group_Analysis
https://doi.org/10.31234/osf.io/a5469
You will have to define a different model for each of your inferences.
Best regards,
Guillaume.
On 09/01/2019 09:11, Johannes Bl öchle wrote:
> Dear SPM community,
>
> I am struggling with selecting the right contrast weights when using a
> second level flexible factorial design with to different groups.
>
> I have a mixed design with two groups:
>
> The between group factor intervention type (2 Levels) x within subject
> factor measurement (2Levels) and a within subject factor condition (3
> Levels).
>
> I am interested in the main effects of group, time and condition and
> particularly in the interaction of time*condition. Unfortunately I am
> struggling to understand how to enter the contrast weights for these
> effects of interest.
>
> I already read the tutorial by Jan Gläscher and Darren Gitelman on that
> topic but I still don't manage to define valid contrasts in the contrast
> manager.
>
> Any help woul be highly appreciated.
>
> Best regards,
>
> Johannes
>
--
Guillaume Flandin, PhD
Wellcome Centre for Human Neuroimaging
UCL Queen Square Institute of Neurology
London WC1N 3BG
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