### 13.7 WEIGHT

         WEIGHT BY var_name.
         WEIGHT OFF.

`WEIGHT` assigns cases varying weights, changing the frequency distribution of the active dataset. Execution of `WEIGHT` is delayed until data have been read.

If a variable name is specified, `WEIGHT` causes the values of that variable to be used as weighting factors for subsequent statistical procedures. Use of keyword `BY` is optional but recommended. Weighting variables must be numeric. Scratch variables may not be used for weighting (see Scratch Variables).

When `OFF` is specified, subsequent statistical procedures will weight all cases equally.

A positive integer weighting factor w on a case will yield the same statistical output as would replicating the case w times. A weighting factor of 0 is treated for statistical purposes as if the case did not exist in the input. Weighting values need not be integers, but negative and system-missing values for the weighting variable are interpreted as weighting factors of 0. User-missing values are not treated specially.

When `WEIGHT` is specified after `TEMPORARY`, it affects only the next procedure (see TEMPORARY).

`WEIGHT` does not cause cases in the active dataset to be replicated in memory.