In reply to Ksharp.

Thanks for asking. Textbooks usually (but not always) define the parameter estimates as a column vector. However, the optimization routines in SAS/IML send in parameters as row vectors to the objective function. Therefore, in the BinLogisticLL function, the input argument b is a row vector. You can either use X*b` or X*colvec(b) to obtain the predicted values. My comment refers to the math; your comment refers to the variables in the IML program. Both are correct, but the emphasis is different.