Use this pane to select a variable from each survey data file or source file that contains a matching value.

A list of all the variables in each of the source files is displayed. Select one variable from each file that contains values that uniquely identify cases. These are the variables that provide a link between the two sets of data. Only cases where the value in these two variables are the same will have their data merged. For example, if you are adding a variable on average salary by job title to a survey of respondent job details, the unique identifier in each source file may be a variable such as Job Title in the first file and Job Titles in the second file.