Hi, Dante-
Well, with my test data here, PC and PCB are not full of zeros, even when using either '-weight_* ..' option. I might have to get your data to see about that?
I also don't know about using the partial correlation ("PC") matrix with the 3dMVM- or 3dMLE-based approach as the next step. Those are using the set of correlation values for comparisons altogether, and I would have thought using the Fisher-Z version of output would be the most useful/appropriate? Is there a specific reason you would prefer the partial correlation?
--pt