NATIONAL ELECTION STUDIES CD-ROM

ONLINE VERSION

     This handout deals with the NES CD-ROM. 
However, NES launched a web site in 1996 which provides
considerable information online. The site home page is
located at:

It contains over 100 items (questions) from the
NES and gives frequencies for these items going back to 
1952, complete with demographic breakdowns and graphs.
The online "Guide" can be searched by keyword for direct
access to tables of interest. There is a related site at

where you can search the NES codebooks, subset data to
take away, and conduct limited statistical analysis
(descriptives, frequencies, simple crosstabs) online. 
For more information, contact nes@umich.edu; tel. 
313-764-5494; fax 313-764-3341; 426 Thompson Street, 
Ann Arbor, MI 48106-1248.


CD-ROM VERSION

     The NES CD-ROM is from the Inter-University
Consortium for Political and Social Research (ICPSR),
the nation's largest distributor of social science
data. The CD covers data from 1948 through 1994. 

     Though it comes with built-in software for
extracting data from and 1948-1994 series for items
which were asked in three or more years, in this course
we will be using the 1994 data with SPSS for Windows.
The 1994 data is located on the CD-ROM in a directory
called NES1994. This directory contains almost 11 MB of
data files. You will not have room to copy it to disk
but will have to work off the CD or a copy on the
network or your hard drive.


Loading NES1994

1. Run SPSS by clicking on its icon.

2. Select File, then Open, then SPSS Syntax. This will
give you a dialog box similar to many Windows packages.
Choose the directory and path in which the NES1994 data
are located. Then highlight and select the file called
NES1994.SPS. This is the data definition file,
containing such things as variable names, value labels,
missing value statements, and transformation
statements. It is very large and will take a long time
to load. 

3. Near the top of the NES1994.SPS file is the DATA
LIST statement:
               DATA LIST FILE= DATA/
This is followed by a list of the variables. Delete the
word "DATA" in this statement and substitute the drive,
path, and name of the NES1994 ASCII data file, which is
NES1994.DAT. For instance:
               DATA LIST
FILE='Y:\PC\CLASS\PA573\NES1994.DAT'/
Note that this has to be enclosed in single quote
marks. Do not save this file (you won't be able to save
back to the CD-ROM, and we ask you not to do so to
copies on the network or a hard drive).

4. Select Edit, then Select, then All. The entire
syntax window will turn inverted color. 

5. Click on the Run icon to run the highlit syntax.
This is the button with the little right-pointing arrow
on the Toolbar (the third row down in SPSS). Note that
as you move the mouse cursor over a Toolbar button, the
function of that button is explained on the status line
(the line at the bottom of the screen). As the file is
very large, it will take a while to run the syntax,
which loads the 6 MB data file. 

6. After Step 5, the status bar will say
"Transformations pending". This is because the bottom
of the NES1994.SPS file contains a RECODE statement for
defining certain values (mostly 0's) as missing for
each variable. Select Transform, then Run Pending
Transformations to execute this operation.

7. At this point the status line (at the bottom) will
say "SPSS Processor is ready. You are now ready to
select Statistics or Graphs -- or you would be if you
knew which variables you wanted! Unfortunately, if you
go directly to Statistics or Graphs, the variable lists
you will see will be things like  V1322' and  V2499'.
There are two ways you can figure out what variables
you will want:

     a. The NES1944 directory on the CD-ROM has a series
     of codebook files which can be loaded into any word
     processor and examined. These give the actual text
     of all questions, the possible answers, and the
     frequencies for each value response. For the
     convenience of the user, the codebook for this
     study has been split into five files each in
     machine-readable ASCII format:

            FILENAME              CONTENTS

        1.  NES94INT.CBK           Table of Contents
                                   Codebook Introduction
                                  Variable List
        2.  NES94V94.CBK           1994 Variable
                                   Codebook Entries
        3.  NES94V92.CBK           1992 Variable
                                   Codebook Entries
        4.  NES94V93.CBK           1993 Variable
                                   Codebook Entries
        5.  NES94APP.CBK           Codebook Appendix and
                                   Notes

     There are codebooks for 1992 and 1993 because
     NES1994 is enhanced with data from these two
     earlier surveys.
     
     B. In SPSS you can select Windows, then click on
     the still-loaded NES1994.SPS file. This brings you
     back to the syntax window (you may still be there
     anyway). If you scroll down this window you will
     find the VARIABLE LABELS statement, listing
     English-type names for each variable. Right after
     this is the VALUE LABELS statement, listing in
     English the names of each value of each variable.
     This is not as informative as the codebooks, but it
     can be used in a pinch.




doc: nescdrom.wp6