Hi Wgao, Repeated measures analysis is not available in EM. I would look into PROC MIXED and PROC GLIMMIX which would enable you to specify specific correlation structures for the observations that come from the same person. Note that if you have a very large data set with large number of predictors, fitting mixed models can be computationally very exhaustive. If that is the case, try HPMIXED which might provide batter performance. Thanks. Funda ... View more