Hello,   I am using SAS University Edition to complete an assignment for my stats class with my partner and I am having an issue. We are trying to fit a heterogeneous error covariance structure to a dataset and have been given some benchmark results to make sure we are on the right track. Unfortunately, my partner and I have exactly the same code (copied directly from a word document) and while he is getting the correct value, I am not. He is using a mac and I'm using a PC and I get the same value in google chrome and internet explorer. Perhaps there is some difference in these two operating systems that I'm unaware of? Any help would be greatly appreciated.   Here is an example of my code:   proc sort data=first; by block var; proc glimmix data=first; class block var; model leaf=var; random block; random _residual_ / subject=block*var group=var; lsmeans var / pdiff adjust=tukey; output out=second predicted=pred student=studentresid student(noblup)=smresid; run; ... View more