The variable in the RANGE statement, the ID variables, and the BY variables are available for the model program to examine, but their values should not be changed by the program.

Health programs that use social and related data obtained through surveys or other methods need to distinguish among so-called independent variables. Three groups of independent variables are (a) ...

A new procedure for mixed integer programming is presented. It is applicable where the integer variables must be either zero or one, and where the integer variables are divided into sets such that the ...