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⇤ ← Revision 1 as of 2007-03-06 12:26:44
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| SPSS does not automatically create dummy variables using the linear regression procedure. Dummy variables are indicator 0-1 used in regressions for representing categorical variables with 3 or more levels. The macro below will produce these prior to entry in a linear regression. Remember to make sure there are no empty categories. | |
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| * Improved version of dummy variable example which doesn't need the number of levels of a categorical variables to be specified | |
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| * Example of reading in a dummy variable without having to specify its maximum value * * features: matrix, nested macro, use of include to read in macro script * * reading in from a specified file |
* reading in from a specified file called GSS1991.sav |
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| Open data file before running e.g using |
SPSS does not automatically create dummy variables using the linear regression procedure. Dummy variables are indicator 0-1 used in regressions for representing categorical variables with 3 or more levels. The macro below will produce these prior to entry in a linear regression. Remember to make sure there are no empty categories.
* * reading in from a specified file called GSS1991.sav
Open data file before running e.g using get file='C:GSS1991.sav'.
define !d1 (!POS !TOKENS(1)
/!POS !CMDEND).
matrix.
get x /var=!1.
compute n=mmax(x)-1.
save {n} /outfile='C:temp.sav' /vars=n.
end matrix.
get file='C:temp.sav'.
WRITE ouTFILE 'C:temp.sps' /"DEFINE !nbcases()"n"!ENDDEFINE.".
exe.
!d2 !1 !2.
!enddefine.
define !d2 (!POS !TOKENS(1)
/!POS !CMDEND).
GET FILE=!QUOTE(!CONCAT('C:', !UPCASE(!2)) ).
INCLUDE FILE='C:temp.sps'.
VECTOR !concat(!1,d) (!nbcases,F3).
LOOP #I=1 TO !nbcases.
COMPUTE !concat(!1,d)(#I)=0.
END LOOP.
LOOP #I=1 TO !nbcases.
DO IF !1 eq #i.
COMPUTE !concat(!1,d)(#I)=1.
END IF.
END LOOP.
exe.
!enddefine.
!d1 race gss1991.sav.