ETAC in 3dttest++ with covariates

Can the ETAC option in 3dttest++ be used with covariates? I am interested in looking at the correlation between a symptom measure and BOLD signal in a task and have been using Clustsim, but would like to supplement the analyses with the new ETAC method.

Thank you!

Hi AFNI staff.

This might’ve gotten lost in the shuffle around Thanksgiving. Any advice on using ETAC with covariate measures would be much appreciated.


Yes, it can. I do not believe it cares about such things, and simply runs the permutation tests from the residuals of the regression/ttest.

  • rick

I’m actually trying to runs something similar. However the two etac masks did not change if I run the t-test with or without covariates. Does this mean that covariates did not affect the t-test? However, what I expected is a mask for the covariates bricks which I did not have.