Hello. We ran 3dMVM with R version 3.2.4 and AFNI version AFNI_16.0.16. It does NOT run with R v. 4.1.1 (or 3.6.3) and AFNI v. AFNI_21.2.04. We suspect that it is a newer version of R and not AFNI, given the model failure error below. Thoughts? Thanks in advance. - Julie
Possible reasons:
0) Make sure that R packages afex and phia have been installed. See the 3dMVM
help documentation for more details.
1) Inappropriate model specification with options -bsVars, -wsVars, or -qVars.
Note that within-subject or repeated-measures variables have to be declared
with -wsVars.
2) Incorrect specifications in general linear test coding with -gltCode.
3) Mistakes in data table. Check the data structure shown above, and verify
whether there are any inconsistencies.
4) Inconsistent variable names which are case sensitive. For example, factor
named Group in model specification and then listed as group in the table header
would cause grief for 3dMVM.
5) Not enough number of subjects. This may happen when there are two or more
withi-subject factors. For example, a model with two within-subject factors with
m and n levels respectively requires more than (m-1)*(n-1) subjects to be able to
model the two-way interaction with the multivariate approach.
** Error:
Quitting due to model test failure...