Dear SPMers,
I am trying to run a 3X3 within-subject ANOVA, with 2 repeated block
sessions for each subject.
I have 2 factors of 3 levels each: 1st factor: Task type (A1,A2,A3), and 2nd
factor: Moment (B1, B2, B3).
Following the examples and data from Rik Henson, (chapter 28 of the SPM
manual, as well as the article of henson and Penny) I tried to declare my
first-level analysis, with 9 conditions, and 2 factors under factorial
design. The only problem is that the sessions and movement parameters are
only declared in the Data& Design section and not in the factorial design.
You can find the job file attached as "1st-level 3X3 within subject ANOVA 2
sessions batch".
Thus, I have a problem with my sessions and the contrasts that are
automatically generated by SPM5 when using the factorial design. I don't
know how else to declare both sessions so that Spm5 can correctly generate
the appropriate contrasts. Running the above job file leads to an Horzcat
problem, I'm guessing SPM does not produce the appropriate contrasts due to
the 2 sessions and their movement parameters.
Does anyone know how to declare multiple sessions in a factorial design so
that Spm can automatically generate the appropriate contrasts?
Thanks in advance for any help.
Alice Gomez
P.S.: If it is not possible to run such analysis, is it correct to generate
the contrasts manually, replicate them over both sessions and then run a
second-level analysis ?
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