Following is my SAS program to build GARCH model using PROC AUTOREG:
proc autoreg data=DATASET;
model Y= X1 X2
/method=ml nlag=12 garch=(p=1,q=1) maxiter=500 dwprob;
run;
I ran this same program using same database in 2 different versions of SAS:
1) Base SAS
2) ETS SAS
Both are giving different GARCH estimates, although AUTOREG estimates are same. Please help why it is so and how to get same outputs?