Hi Everyone,  Thanks for taking the time to read this.  I'm having a bit of trouble with PROC MIXED -namely when modeling an interaction term between a continuous and binary variable.  The model part of my code reads like this:    model result = arm_studyall*visit_m arm_studyall visit_m /solution;  For clarity result is a continuous variable. arm_studyall is a binary variable and visit_m is a continuous variable. When I execute my code the fixed part of the model produces an interaction term for both levels of the binary variable I'm not quite sure why this is happening -as I would expect only one interaction term to be estimated.  Any insight would be helpful.  Thanks again.    ... View more