A quick google on "combining log likelihoods" gives a lot of interesting results ranging from as simple as adding the log likelihoods (equivalent of multiplying the likelihood) which assumes independence between the imputations, to several Bayesian methods, and on to some good Q and A on stackexchange.   The one thing I thought was a common thread is that there is good theory behind the adding of log likelihoods/multiplying likelihoods when you think of it as combining probabilities.  There is a strong independence assumption though.   SteveDenham ... View more

Hello @ejamro ,   I haven't used PROC MI for 6 or 7 years now, but at the time , there was no specific adjustment in Proc MI for an HLM type model (multi-level model).  The problem is that there is no widely accepted approach to deal with an HLM model and multiple imputation (afaik).     You may open a track / ticket with SAS Technical Support. Maybe they can tell you more. Maybe something has been foreseen meanwhile to do this.   Thanks, Koen ... View more

@ejamro wrote: Thanks for your reply. Is there some trick to using proc stdize on imputed data? The resulting mean is very close to zero when I use proc mi and then proc stdize (for example, mean=-8.19047E-16), but it isn't exactly zero as I'd expect. There is no trick. Your mean is zero except for roundoff error. Nothing to worry about. ... View more