Contrast specification (3dANOVAx, 3dMVM)

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Dear AFNI experts,

I have a question regarding afni’s statistical tools:
I have three beta maps per subject corresponding to three condition, I want to know if at least in one condition I have a beta value above 0. Which corresponds to a contrast matrix equal to diag(3) (H0: Level1=Level2=Level3=0).
I used 3dMVM with -glfLabel 1 level_ftest -glfCode 1 ‘level : 1level_1 & 1level_3 & 1*level_5’ but I’m not sure about that.

Did I do my statistical test correctly or not? Can I use the 3dANOVAx suite?

Thank you,
Roberto

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Greetings Roberto,

I used 3dMVM with -glfLabel 1 level_ftest -glfCode 1 ‘level : 1level_1 & 1level_3 & 1*level_5’ but I’m not sure about that.

The specification is correct. However, 3dMVM can only properly perform such an F-test for a between-subjects factor. To run such an F-test for a within-subject factor in your case, use 3dLME with the same -glfCode specification.