The SSM Procedure

BY Statement

  • BY variables;

A BY statement can be used in the SSM procedure to process a data set in groups of observations that are defined by the BY variables. The model specified by using the MODEL and other statements is applied to all the groups defined by the BY variables. When a BY statement appears, the procedure expects the input data set to be sorted in order of the BY variables. The BY variables are one or more variables in the input data set. The BY variables cannot be used in the model specification; in particular, they cannot be used as response variables or regressors in a MODEL statement.