# st: A contingency table of counts by case

 From Serguei Kaniovski To statalist@hsphsun2.harvard.edu Subject st: A contingency table of counts by case Date Mon, 11 Sep 2006 16:36:40 +0200

I have the following data:

case id x
1 1 1 1
2 1 2 1
3 1 3 1
4 2 1 1
5 2 2 0
6 2 3 1
7 3 2 1
8 3 3 0
9 3 4 0

"case" - cases, "id" - persons, and "x" - binary state.

I would like to count the number of "cases" in which any two "id"

a. both have "x=1",
b. the first has "x=0" - the second has "x=1",
c. the first has "x=1" - the second has "x=0",
d. both have "x=0",

and transform these counts to relative frequencies in the total number of "cases" the pair has been observed together. The composition of "case" by "id" varies, e.g. case=1,2 have id=1,2,3, but case=3 has id=2,3,4.

I guess this can be accomplished using nested loops, but do you know of a better solution? I have about 20000 observations.

Thanks a lot for you help,
Serguei Kaniovski
--
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Austrian Institute of Economic Research (WIFO)

Name: Serguei Kaniovski P.O.Box 91
Tel.: +43-1-7982601-231 Arsenal Objekt 20
Fax: +43-1-7989386 1103 Vienna, Austria
Mail: Serguei.Kaniovski@wifo.ac.at

http://www.wifo.ac.at/Serguei.Kaniovski

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