# [R] Index of predictive association

s-luppescu@uchicago.edu s-luppescu at uchicago.edu
Fri Aug 11 21:44:48 CEST 2000

```I need to calculate an index of predictive association, similar to Goodman and
Kuskal's (1954) for a 2x2x2 array. I have two questions:
1) Is there an easy way to do this in R? (Of course, the answer to this kind of
question is nearly always ``yes.'' Perhaps I should have asked, ``How can I do
this in R?'')
2) Is it reasonable to try this with a 3-dimensional array? The way I thought
of doing it (say, the variables are x, y, and z, with z being the
outcome) involves calculating the probability of z_i conditional on knowing
both x and y. This leads to some funny stuff, which makes me doubt if I'm doing
it right. Perhaps I should condition on only one of x and y at a time?

Any help would be appreciated.
______________________________________________________________________
Stuart Luppescu         -=-=-  University of Chicago
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>> Sent on 11-Aug-2000 at 14:36:43 with xfmail
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