Creating a Data Definition File

Abstract

Creating a data file, containing only the data, is just a first stage towards using SPSS/PC+. The data must be defined (and is also usually more fully described) before it can be used. The data is defined in a data definition file. This usually contains the following types of command:

• DATA LIST: a list which gives the names of all of the variables represented by the data, in the order that they occur, and information about which column(s) each variable occupies

• VARIABLE LABELS: (optional) variable labels should not be confused with the variable names specified on the DATA LIST

• VALUE LABELS: (optional) value labels for some or all of the values for each variable

• MISSING VALUE: information about which value, if any, represents missing data for each variable

There are few rules in SPSS/PC+ about the order in which the above commands are entered, but there is one rule which is very important. A variable must be declared in a DATA LIST command before any labels are provided for it or a missing value specified for it.