Since I am a bit at a loss here, let me suggest trying 2 things for comparison.
1. Remove the extra ETAC options, and simply add -ETAC to the normal 3dttest++ command.
2. Try this with our data. Download AFNI_data6.tgz and add -ETAC to an existing 3dttest++ script.
afni_open -aw AFNI_data6.tgz
tar xfz AFNI_data6.tgz
cd AFNI_data6/group_results
# then edit script s6.ttest.covary, adding -ETAC to the 3dttest++ command, and run:
tcsh -x s6.ttest.covary
That would not take too long, and it would give you something to compare with.
Does that seem reasonable?
- rick