afni.nimh.nih.gov

> So just to be clear, ranEff "~1" will estimate random intercepts for any variables specified in the
> dataTable that are NOT in the model?

No, the current implementation in 3dLME only considers "subjects" as the only random-effects variable.

> Site, family ID and sibling are nested (and not crossed) random effects. The data were collected
> at multiple sites and contains siblings (i.e., family_ID) and twins/triplets (i.e., sib). There are
> different numbers of subjects and siblings/twins per site. Therefore, we want to include these
> factors as nested random effects.

An intricate dataset!

1) How many subjects do you have within each site?
2) How families? Are they all twins/triplets? Do you differentiate monozygotic (MZ) and dizygotic (DZ) twins/triplets?

Gang