README.TXT


The 1956 NES Study is released with the following files:


     RAW DATA AND SAS/SPSS DATA DEFINITION FILES
     -------------------------------------------
     NES1956.DAT    ASCII data for use with SAS/SPSS data definition file
     NES1956.SPS    SPSS data definition file
     NES1956.SAS    SAS data definition file


     SPSS PORTABLE FILE
     ------------------
     NES1956.POR    SPSS portable (transport) file


     SAS TRANSPORT FILE
     ------------------
     NES1956.TRA    SAS portable (transport) file **


     CODEBOOK
     --------
     INT1956.CBK    CODEBOOK INTRODUCTORY MATERIAL
     NES1956.CBK    CODEBOOK VARIABLE DOCUMENTATION
     APP1956.CBK    CODEBOOK APPENDIX MATERIAL


In addition, the file NES1956.TXT is included for users who wish to use
the NES data with the NESstat software included on the 1948-1997
NES CD-ROM.


**SAS TRANSPORT FILE NOTES:
--------------------------

Due to the manner in which SAS handles missing data definitions, the 
SAS transport file does not have in effect the missing data definitions 
found in the .SAS data definition file.
This transport file includes the formats catalog for predefined formats, 
which must be placed in an appropriately identified library.
The SAS transport file was created using PROC CPORT and must be imported 
using PROC CIMPORT (not Proc Copy).  PROC CIMPORT WILL create both the .sd2
system file and formats.sc2 catalog file.  In Windows the commands would be
(for example):
    libname copy 'c:\copy';
    run;    filename trans 'c:\download\nes1956.tra';
    proc cimport library=copy infile=trans;
    run;
(For other operating systems, the location and file naming conventions will 
differ.) The libname statement is for the location to place the .sd2 and
formats.sc2 files.  The filename statement assigns the tag 'trans' to the
location-filename of the transport file itself.


=============================================
USERS ARE ADVISED TO READ THE FOLLOWING NOTES:
=============================================

NOTE ON VARIABLE NAMING:

The variable name references used in NES Study codebooks do not include 
the "V" prefix found in all variable names used within the released 
SAS and SPSS data definition files (.sas and .sps files).

For example, "VAR 920001" and "VAR VERSION" in Study codebooks refer to
V920001 and VVERSION in the study data definition files.



SPECIAL NOTE ON COLUMN LOCATIONS:

Some numeric variables use coding schemes that allow for code values
having a varying number of digits. In such instances, the number
of columns corresponding to the variable in the data file [.dat file] 
and in the column specifications  will be the width of the maximum value
occurring in the actual data, rather than the maximum width allowable
by the coding scheme.  For example, if codes 01-12 are allowed for a
numeric variable but all values in the data are less than 10, then the
number of columns corresponding to the variable within the ASCII data 
file will be 1.                                                                                                                              
