I wish to estimate expenditure on a sub-sample, and use the estimates to predict expenditure for the entire sample. So in the first stage, I regress: proc reg data=InputData outest=estimates;   model Exp = lnY lnY_2 &ivset ;   where Exp ge  100;   output out=Pred_Exp p=predexp; run; The problem is I then have to manually use the parameter estimates to predict expenditure for the cases with Exp<100. Is there a shorter way to do this than manually using the parameter estimates that I have saved to the dataset estimates? ... View more