Counting missing values
Records whose values are missing_ fail all the standard conditions on a val statement. To create an element on a val statement that counts missing values, enter the condition as missing_. For example:
l rental
val c(9,10);Base;i;None=0;1-5;6-10;11-20;21-30;31+;
+=;DK/NA=missing_
In this example, the DK/NA element counts any record in which c(9,10) is not numeric.
See also