SPSS® 12.0 Command Syntax Reference

1480 SELECT IF
Missing Values
• If the logical expression is indeterminate because of missing values, the case is not selected.
In a simple relational expression, a logical expression is indeterminate if the expression on
either side of the relational operator is missing.
• If a compound expression is used in which relations are joined by the logical operator OR,
the case is selected if either relation is true, even if the other is missing.
• To select cases with missing values for the variables within the expression, use the
missing-value functions. To include cases with values that have been declared usermissing
along with other cases, use the VALUE function (see p. 53 in Volume I).
Limitations
Example
Example
SELECT IF cannot be placed within a FILE TYPE—END FILE TYPE or INPUT PROGRAM—END
INPUT PROGRAM structure. It can be placed nearly anywhere following these commands in
a transformation program. See Appendix A for a discussion of program states and the placement
of commands.
SELECT IF (SEX EQ ’MALE’).
• All subsequent procedures will use only cases in which the value of SEX is MALE.
• Since upper and lower case are treated differently in comparisons of string variables, cases
for which the value of SEX is male are not selected.
SELECT IF (INCOME GT 75000 OR INCOME LE 10000).
• The logical expression tests whether a case has a value either greater than 75,000 or less
than or equal to 10,000. If either relation is true, the case is used in subsequent analyses.
Example
SELECT IF (V1 GE V2).
• This example selects cases where variable V1 is greater than or equal to V2. If either V1
or V2 is missing, the logical expression is indeterminate and the case is not selected.