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Hi Esther, In the 1st level, the contrasts you already have are: S11 vs S21: 1 0 -1 0 S12 vs S22: 0 1 0 -1 Now you'd just add, for each subject: (S11 vs S21) vs (S12 vs S22): 1 -1 -1 1 It should do what you need. These can be passed up to the higher level and used to make group inferences. All the best, Anderson On 27 August 2015 at 14:23, Esther Heckendorf < [log in to unmask]> wrote: > Hi, > > I have a question about the set up of a three level analysis in FSL. I > have two stimuli with each two levels (S11, S12, S21, S22) and I have > created the contrasts S11 vs. S21 and S12 vs. S22 in the lower-level > analyses. Now, I would like to calculate the following contrast: (S11 vs. > S21) vs. (S12 vs. S22). Is it possible to calculate this contrast in a > higher-level analysis using the COPEs of the contrasts S11 vs. S21 > (contrast 1) and S12 vs. S22 (contrast 2) as inputs? For an example with 3 > participants I would set up the following model: > > EV1 EV2 EV3 > Input 1 1 0 0 > Input 2 0 1 0 > Input 3 0 0 1 > Input 4 -1 0 0 > Input 5 0 -1 0 > Input 6 0 0 -1 > > Input 1 = First contrast for subject 1 > Input 2 = First contrast for subject 2 > Input 3 = First contrast for subject 3 > Input 4 = Second contrast for subject 1 > Input 5 = Second contrast for subject 2 > Input 6 = Second contrast for subject 3 > > Contrasts and F-tests: > EV1 EV2 EV3 > subject 1 1 0 0 > subject 2 0 1 0 > subject 3 0 0 1 > > Is it possible to calculate the contrast (S11 vs. S21) vs. (S12 vs. S22) > in this way or is it necessary to set up the model for each subject > separately? > > Thanks, > Esther >