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VAR CF0009 TYPE 0 WEIGHT
COLUMNS 24-29
NUMERIC DEC 4
NO MISSING DATA CODES
GENERAL WEIGHT VARIABLE 1
-------------------------------------------------------------------
NOTE ON USE OF WEIGHTS:
~~~~~~~~~~~~~~~~~~~~~~
SEE ALSO SUMMARY CHART BELOW.
THERE ARE 9 WEIGHT VARIABLES IN THE CUMULATIVE DATA FILE:
VCF0009 VCF0010 VCF0011
VCF0009a VCF0010a VCF0011a
VCF0009b VCF0010b VCF0011b
1. IMPORTANT: CASES FROM YEARS OTHER THAN 1970, 1994 OR LATER
HAVE IDENTICAL VALUES IN ALL (9) WEIGHT VARIABLES. WHEN DATA
FOR YEARS EXCLUDING 1970 AND 1994-LATER ARE USED FROM THE
CUMULATIVE DATA FILE, ANY OF THESE WEIGHT VARIABLES MAY BE
UTILIZED TO OBTAIN THE SAME RESULTS.
2. WHEN CUMULATIVE DATA FILE VARIABLES INCLUDE 1970 DATA AND/OR
DATA FROM 1994 AND LATER, WEIGHT SELECTION SHOULD BE BASED UPON
3 CONDITIONS:
A) THE 'TYPE' OF 1970 VARIABLE
B) WHETHER POST-STRATIFIED OR NON-POST-STRATIFIED WEIGHTING
IS USED 1994 AND LATER
C) FOR PRE-POST STUDIES WITH POST-STRATIFIED WEIGHTS
AVAILABLE (E.G. 1996), WHETHER STUDY DATA ARE PRE OR
POST.
1970
----
The original study data for 1970 were weighted by variable
type; there were 3 types of 1970 variables: Type 0, Type 1,
Type 2.
Most 1970 variables were Type 0. A list of Cumulative Data File
variables that include 1970 Type 1 or 1970 Type 2 data are
identified in documentation for VCF0010 and VCF0011; all other
Cumulative Data File variables that include 1970 data are assumed
to be Type 0 data for 1970.
Note: documentation in this codebook identifies for each
variable containing 1970 data the 'type' of 1970 weight to use
(except demographic variables, which are Type 0).
Weighting Cumulative Data File variables that include 1970
data means selecting the appropriate weight for the type of
1970 variable represented in the Cumulative Data File variable.
For each of the 3 types of 1970 variables, there are 3
Cumulative Data File weight variables which have identical
values for 1970 cases:
CDF VAR CDF VAR CDF VAR
INCLUDES 1970 INCLUDES 1970 INCLUDES 1970
TYPE 0 DATA - TYPE 1 DATA - TYPE 2 DATA -
USE ONE OF: USE ONE OF: USE ONE OF:
~~~~~~~~~~~ ~~~~~~~~~~~ ~~~~~~~~~~~
VCF0009 VCF0010 VCF0011
VCF0009a VCF0010a VCF0011a
VCF0009b VCF0010b VCF0011b
If no 1994 or later cases are selected in combination with 1970
cases, then it does not matter which of the 3 weight variables
for that type is used. For example: if 1970 data are Type 0 and
no 1994 or later data are included, then any of the following
weights can be used to produce the same results: VCF0009/9a/9b.
Choice among the 3 variables for each 1970 'type' is determined
by the kind of weighting desired for years 1994 and later.
1994 AND LATER
--------------
1994 and later data have more than one type of weighting
available. Each type of weighting is found identically in
3 variables for these years:
1994-LATER
WEIGHTING TYPE WEIGHT VALUES SAME IN 3 VARS:
~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
NOT POST-STRATIFIED VCF0009, VCF0010, VCF0011
POST-STRATIFIED - PRE* : VCF0009a, VCF0010a, VCF0011a
POST STRATIFIED - POST* : VCF0009b, VCF0010b, VCF0011b
In Pre-Post studies after 1994, there were 2 post-stratified
weights, one for pre-election variables and one for post-
election variables. Cumulative Data File "a" weight variables
(VCF0009a,VCF0010a,VCF0011a) are identical and contain the weight
values appropriate for weighting pre-election variable data from
these years; Cumulative Data File "b" weight variables (VCF0009b,
VCF0010b,VCF0011b) are identical and contain the weight values
appropriate for weighting post-election variable data from
these years (choice among VCF0009a/VCF0010a/VCF0011a or choice
among VCF0009b/VCF0010b/VCF0011b is determined by type of 1970
data which are also included; if no 1970 data are also selected,
then any variable from each set may be used).
* Post-election studies beginning 1994 (e.g. 1994 or 1998) did
not have a pre post-stratified weight, thus the "a" and "b"
variables are identical for post-election studies (e.g, VCF0009a
and VCF0009b are the same for 1994 or 1998).
SPECIAL NOTE FOR POST-STRATIFIED WEIGHTING 1994-LATER:
For an individual Cumulative Data File variable, data from pre-
post studies after 1994 (e.g. 1996 and 2000) may not be uniformly
Pre or Post. Thus it is possible, for example, that 1996 data
would be pre data but 2000 data would be post data for the same
Cumulative Data File variable. This would make difficult the
utilization of a single post-stratified weight across these
years. Users could construct additional weights covering various
combinations (e.g. 1996 pre weighting and 2000 post weighting or
1996 post weighting and 2000 pre weighting). An alternative would
be for users to examine the differences between estimates produced
using pre- election versus post-election post-stratified weights.
Although the post-election post-stratified weights provide the
most complete adjustment for post-election variables from pre-post
studies after 1994, the user may decide that the difference in
estimates produced using pre post-stratified weighting versus post
post-stratified weighting for the post-election variables is small
enough to justify using pre-election post-stratified weights for
all data from these years.
WEIGHT USE SUMMARY
~~~~~~~~~~~~~~~~~~
DESIRED TYPE OF || 1970 | 1970 | 1970 | NO
WEIGHTING FOR YEARS || TYPE 0 | TYPE 1 | TYPE 2 | 1970
1994 AND LATER: ** || DATA | DATA | DATA | DATA
=========================||=============================================
|| | | | any of:
non-post-stratified || | | | VCF0009,
|| VCF0009 | VCF0010 | VCF0011 | VCF0010,
|| | | | VCF0011
-------------------------||---------------------------------------------
1) post-stratified for || | | |
Post-election study || | | | any of:
OR || | | | VCF0009a,
2) post-stratified for || VCF0009a | VCF0010a | VCF0011a | VCF0010a
Pre-Post study || | | | VCF0011a
Pre-election variable || | | |
-------------------------||---------------------------------------------
1) post-stratified for || | | |
Post-election study || | | | any of:
OR || | | | VCF0009b
2) post-stratified for || VCF0009b | VCF0010b | VCF0011b | VCF0010b
Pre-Post study || | | | VCF0011b
Post-election variable|| | | |
-------------------------||---------------------------------------------
|| any of: | any of: | any of: |
no data 1994 or later || VCF0009 | VCFOO10 | VCF0011 | any CDF
|| VCF0009a| VCF0010a| VCF0011a| weight
|| VCF0009b| VCF0010b| VCF0011b|
** see "SPECIAL NOTE FOR POST-STRATIFIED WEIGHTING 1994-LATER" (above)
ADDITIONAL NOTES
~~~~~~~~~~~~~~~~
1970 notes:
Black respondents were asked all questions. White respondents
were assigned to one of two formats of the questionnaire. Each
format of questionnaire excluded a selection of questions if the
respondent was white; the questions excluded differed in each
format. The two formats of the questionnaire were designated
Form 1 and Form 2.
'Type 0' describes variables for questions which were not excluded
in either questionnaire format. 'Type 1' describes variables for
questions excluded from Form 2, and 'Type 2' describes variables
for questions excluded from Form 1.
All 1970 vars not listed in VCF0010 as type 1 or in VCF0011 as type
2 are type 0; documentation for each Cumulative Data File variable
in this codebook provides the type of 1970 data utilized (if any).
1994 and later notes:
The first time-series weight variables produced for the 1994 and
1996 studies did not correct for an underrepresentation in Study
data of younger and less-educated respondents (primarily an effect
of the empanelling design used 1992 to 1996; see the 1994 and 1996
codebook special weight documentation). New weight variables were
therefore produced for 1994 and 1996, constructed to post-stratify
the NES data to match the Current Population Study (CPS) estimate
of the distribution of age group by education level. Since 1996
was a 2-wave study, one new weight was constructed for 1996 Pre
variables and a second for 1996 Post variables. After 1996, the
same type of post-stratified weights were constructed, a single
weight for post-election studies and both a pre weight and a post
weight for pre-post studies.
____________________________
VCF0009 DATA:
1948: All cases weighted 1
1952: All cases weighted 1
1954: All cases weighted 1
1956: All cases weighted 1
1958: 580003
1960: 600003
1962: All cases weighted 1
1964: All cases weighted 1
1966: All cases weighted 1
1968: All cases weighted 1
1970: All cases weighted 1, TYPE 0 QUESTIONS
1972: All cases weighted 1
1974: 742003
1976: 763003
1978: All cases weighted 1
1980: All cases weighted 1
1982: All cases weighted 1
1984: All cases weighted 1
1986: All cases weighted 1
1988: All cases weighted 1
1990: All cases weighted 1
1992: 927000
1994: 940006
1996: 960005
1998: All cases weighted 1
2000: All cases weighted 1
==============================
Walter Mebane
2003-02-17