Molly McPup

Introduction to Research Methods in Political Science:
The POWERMUTT* Project
(for use with SPSS)

*Politically-Oriented Web-Enhanced Research Methods for Undergraduates — Topics & Tools
Resources for introductory research methods courses in political science and related disciplines



From the menu bar, click on “Analyze,” then on “Descriptive Statistics,” and on “Explore….”  In the left window, select the variable(s) you wish to analyze, and click on the top right arrow (next to “Dependent List:”).

If you wish to obtain separate plots and statistics for different subgroups of cases, select the variables needed to define your groups from the list in the left window, and click on the second right arrow (next to “”Factor List:”).

By default, EXPLORE produces a stem and leaf plot.  If you wish a histogram instead of or in addition to the stem and leaf plot, click on “Plots…,” make your selections, and click on “Continue.”

EXPLORE provides three alternatives for handling missing data.  Listwise deletion means that if a case has missing data for any of the variables selected, it will be deleted from all calculations.  This insures that all statistics will be based on the same cases, but will eliminate a case from all calculations even if it is missing data for only one or two variables.  Another option is pairwise deletion.  Pairwise deletion means that each statistic will be based on all case with non-missing values for the two variables in question.  This has the advantage of using as much information as possible for the calculation of each statistic.  The disadvantage is that the statistics may not be based on the same subset of cases, since different cases may be missing data for different variables. A final alternative is to report missing values.  If you only have a small proportion of missing data, it will not make much difference which option you choose.  If you have a lot of missing data, no option is very satisfactory.  The default option for EXPLORE is listwise deletion. If you wish to use either of the alternatives just described, click on “Options” and select the option you prefer.

Click on “Continue” (if you have not already done so) and on “OK.”


Last updated April 28, 2013 .
© 2003---2013  John L. Korey.  Licensed under a  Description: Creative Commons License Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License.