On 09/05/2007 5:11 PM, Bingshan Li wrote: > Hi, all, > > I am wondering if there is an algorithm for calculating power of 2x3 > table using Fisher exact test. There is one (algorithm 280) for 2x2 > Fisher exact test but I couldn't find one for 2x3 table. If we are > not lucky enough to have one, is there any other way to calculate > exact power of 2x3 table? The reason why I want exact power is > because some cells are assumed to be very small and chi square > approximation is not valid.
I think there are lots of possible alternatives to the null in a 2x3 table, so you may have trouble finding a single answer to this question. But assuming you have one in mind, I'd suggest doing a Monte Carlo power calculation: simulate a few thousand tables from the alternative distribution, and see what the distribution of p-values looks like. Duncan Murdoch ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
