Hi everybody,
My experiment have one within-subject factor which included four conditions. For the main effect for this one-way repeated measure ANOVA, I got one question:
I had performed 1st level contrast [1 1 1 1] for each subject and put them into 2nd analysis with a one-sample t-test. At the same time, I found (reference: https://en.wikibooks.org/wiki/SPM/Group_Analysis) that [1 1 1 1] refers to an overall effect, which seems to be different from the main effect. For that, i used the function spm_make_contrasts, and the output for the main effect is [1 -1 0 0; 0 1 -1 0; 0 0 1 -1], but this contrast matrix will cause a error "size mismatch" when i re-run the 1st level contrast.
Does anyone get an idea for this?
Thanks in advance.
Look forward.
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