Thanks for the quick answer, that's what I was thinking too. Just wasn't sure wether this was a bug or a matter of computations becoming singular. Florian
> 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 > mantelhaen.test(round(x/s), exact=TRUE) > 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. > > -thomas > ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
