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This example analyzes 32
items selected
from the 48-item version of the Jenkins Activity Survey for
Health Prediction, Form B (Jenkins, Rosenman, and Zyzanski,
1972). The data are responses of 598 men from central Finland
drawn from a larger survey sample. Most of the items
are rated
on three-point scales representing little or no, occasional,
or frequent occurrence of the activity or behavior in question.
For purposes of the present analysis, the scales have been
dichotomized near the median. Wording in the positive or negative
direction varies from item to item as follows (item numbers
are those of the original pool of items
from which
those of the present form was selected):
-Q156,-Q157,+Q158,-Q165,-Q166,-Q167,+Q247,+Q248,-Q249,-Q250,+Q251,+Q252, +Q253,+Q254,+Q255,+Q256,+Q257,-Q258,-Q259,+Q260,+Q261,+Q262,+Q263,+Q264,
+Q265,-Q266,+Q267,+Q268,+Q269,+Q270,+Q271,+Q272,-Q273,-Q274,-Q275,+Q276,
+Q277,+Q278,-Q279,-Q280,+Q307,+Q308,+Q309,+Q310,+Q311,-Q312,-Q313,-Q314.
For a complete discussion
of the contents of the data file and variable format statement
used to read these data, see here.
In a previous
example, EAP factor score estimation was performed. This
example, illustrating MAP factor score estimation, imports
the exampl03.par file from the previous example (FILE
keyword on the SCORE command) to score the respondents to
the survey using the VARIMAX rotated factor pattern (see Example
3).
The PROBLEM, RESPONSE,
KEY, SELECT and INPUT statements are the same as used in Example
3, with the exception of the addition of the SKIP keyword
on the PROBLEM command. Classical item analysis is skipped,
and the removal of the TETRACHORIC, FACTOR and FULL commands
confirms that item factor analysis is also skipped, as indicated
by SKIP =2. The SAVE command is still present, but only used
to save factor scores here.
The SCORE command now indicates
the use of MAP estimation
(METHOD = 3). The FILE keyword indicates the parameter file
to be used while the NFAC keyword indicates the number
of factors
used when estimating the factor scores (recall that in the
previous example 3 factors were extracted). Factor scores
for the first 20 cases are to be written to the output file
(LIST = 20) and the convergence for the MAP iterations is
set by the SPRECISION keyword.
Cases will be scored by
the MAP (Maximum A Posteriori, or Bayes Modal) method. Standard
error estimates will be computed from the posterior information
at the estimated values. The estimated factor scores are saved
to the file exampl03.fsc (FSCORES keyword on the SAVE
command).
>TITLE
ITEMS FROM THE JENKINS
ACTIVITY SURVEY
SCORING THE RESPONDENTS
(MAP METHOD)
>PROBLEM NITEM=48,SELECT=32,RESPONSES=5,NOTPRESENTED,SKIP=2;
>NAMES Q156,Q157,Q158,Q165,Q166,Q167,Q247,Q248,Q249,Q250,Q251,Q252,
Q253,Q254,Q255,Q256,Q257,Q258,Q259,Q260,Q261,Q262,Q263,Q264,
Q265,Q266,Q267,Q268,Q269,Q270,Q271,Q272,Q273,Q274,Q275,Q276,
Q277,Q278,Q279,Q280,Q307,Q308,Q309,Q310,Q311,Q312,Q313,Q314;
>RESPONSE '8','0','1','2','.';
>KEY 002000220022222220022222202222220002220022222000;
>SELECT 3,5,6,7,9,11(1)14,17(1)23,25(1)30,32,33,35,36,39(1)42,47,48;
>SAVE FSCORES;
>SCORE METHOD=3,LIST=20,NFAC=3,SPRECISION=0.0001,FILE='EXAMPL03.PAR';
>INPUT NIDW=10,SCORES,FILE='EXAMPL03.DAT';
(10A1,T1,48A1)
>STOP
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