IBM SPSS Essentials, 2nd Edition

14Collapsing and Merging Data Files

Chapter Menu

• Chapter Learning Objectives
• Same People, Different Information
• Different People, Same Information
• Summary

Chapter Learning Objectives

1. Combining data files: same people, different variables
2. Combining data files: different people, same variables

This chapter is something of an advanced course in the use of the “get file” and “save outfile” commands. Here you will learn more about controlling the constituency of your data files. There are two primary reasons you would use the information in this chapter: (1) you have two or more data files with different information from the same individuals, or (2) you have two or more data files with similar information from different individuals. In both scenarios you ultimately want to get the files together.

The first situation is exemplified (in our field, for example) by one data file that contains applicant characteristics (typically applicants' scores on selection assessments) and another data file that contains job performance information (collected at a later time from those same applicants, now actual employees). Eventually, you'll need to combine these two files if you want to do anything meaningful with the information.

The second situation is typified by students who we recruit to help us with research projects. Any given semester, these student research assistants enter ...