09-26-2012 10:35 PM
I am trying to get SAS to print out its dummy coding structure using proc glm, because I am assuming it's using the last categorical variable as the reference variable with 0 0 0 (I have 3 treatment groups) and additionally, how would I change it so instead of 0s for the reference variable I have -1s?
09-27-2012 10:19 AM
You can obtain the dummy variable coding from PROC GLMMOD.
You can't change the dummy variable coding used by PROC GLM, however if you want a level to be -1 and another level to be +1, you can achieve this via the CONTRAST statement of PROC GLM.