User Guide

189
Modifying Data
Values
You can also link two or more conditional expressions using logical operators, as in:
age>=21 | ed>=4
or
income*3<100 & ed=5
In the first example, cases that meet either the Age (age) condition or the Level of
education (ed) condition are selected. In the second example, both the Household
income in tho
usands (income) and Levelofeducation(ed)conditions must be met for
a case to be selected.
Computing V
ariables with Missing Values
When comput
ing variables with missing values, it’s a good idea to perform a trial
on a small data file in order to ensure that your missing data are handled in a way
that is acceptable. Some computations handle missing data by removing them from
the equati
on, while others cannot perform the computation and the new value is
considered missing. The following examples use car_sales.sav.
There are two different ways to compute the mean of a set of variables. The first is
to divide t
hesumofthesetofvariablesbythenumberofvariablesintheset.
E From the m
enus choose:
Transform
Compute...
E
Type avgsale in the Target Variable text box.