[R] exact conditional mantelhaen.test estimate is 0 ?!
tlumley at u.washington.edu
Fri Jul 8 19:34:19 CEST 2005
On Fri, 8 Jul 2005, Florian Hahne wrote:
> Dear listers,
> I am trying to compute the exact conditional test given strata margins
> of a 2 by 2 by K array using the mantelhaen.test function to get a
> common odds ratio estimate.
> The estimate for the test on the following data is 0, which in my
> opinion dosen't make any sense.
Indeed it doesn't. Some probabilities are underflowing to zero. It is
informative to look at the estimates from
for various values of s. The estimate is stable at about 0.04 for
large s until s gets to just above 1.8, then quickly decreases to zero.
I think you need exact=FALSE for data sets this large.
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