Quantitative variables take the form of numerical figures. Qualitative variables describe data by placing them into broad categories. For example, the number of units that your business sells over a ...

A two-valued qualitative variable can be represented by a single 0-or-1-valued "dummy" variable. If a qualitative variable has three or more possible values (e.g., make-of-car, or marital-status), ...

1If not explicitly defined, a variable's type and length are implicitly defined by its first occurrence in a DATA step. 2The minimum length is 2 bytes in some operating environments, 3 in others. See ...