You can use a series of programming statements that use variables in the input data set that you specify in the DATA= option in the PROC SEVERITY statement to assign a value to an objective function symbol. You must specify the objective function symbol by using the OBJECTIVE= option in the PROC SEVERITY statement. If you do not specify the OBJECTIVE= option in the PROC SEVERITY statement, then the programming statements are ignored and models are estimated using the maximum likelihood method.
You can use most DATA step statements and functions in your program. Any additional functions, restrictions, and differences are listed in the section Custom Objective Functions.