3dMVM output question

Hello experts! I am working with a 2 (between subjects) x2 (within subjects) x3 (within subjects) project. I have added 2 GLFs to the model to look at sub-interactions. I am confused that the output buckets for these sub-interactions say Z next to their title in afni viewer, instead of F like the automatic F tests calculated and their corresponding buckets. My understanding is that the output buckets for the sub-interactions should be F statistics but seeing the Z in the bucket titles is making me question whether that is the case. The distribution of the sub-interactions are also positive only, which similarly makes me think they are F distributions. I would appreciate clarification on this! Thank you!

Are you talking about 3dMVM or 3dLME/3dLMEr? What is your AFNI version?

afni -ver

Hi! Thanks for your response! It’s 3dMVM and afni version 21.3.06 ‘Trajan’. I’m attaching screenshots of part of the script and the afni viewer incase helpful.
The three variables are grp (dep, ctrl), time (pre, post), and valence (pos, neg, neu). Thank you!

It’s 3dMVM and afni version 21.3.06 ‘Trajan’.

It’s likely due to an old version of 3dMVM. Update your AFNI:

@update.afni.binaries -d

Those 2 lines of GLFs can be added to your GLTs since they are essentially comparisons with one degree of freedom.

Thank you Gang!! I appreciate it :slight_smile: