On Apr 14, 2011, at 01:29 , (Ted Harding) wrote: > On 13-Apr-11 17:40:53, Jim Silverton wrote: >> I have a matrix say, >> >> 1 4 >> 23 30 >> >> and I want to find the previously attainable fisher's exact test >> p-value. Is there a way to do this in R? >> -- >> Thanks, >> Jim. > > I do not understand what you mean by "previously attainable". > > As far as that particular matrix is concerned, the fisher.test() > function will yield its exact Fisher P-value: > > M <- matrix(c(1, 4, 23, 30), byrow=TRUE, nrow=2) > M > # [,1] [,2] > # [1,] 1 4 > # [2,] 23 30 > fisher.test(M) > # Fisher's Exact Test for Count Data > # data: M > # p-value = 0.3918 > # alternative hypothesis: true odds ratio is not equal to 1 > # 95 percent confidence interval: > # 0.006355278 3.653391412 > # sample estimates: > # odds ratio > # 0.3316483 > > So the P-value is 0.3918 (as attained now, and as attainable > at any time previously if you had done the above ... !). >
What Ted said, plus f <- fisher.test(M) f$p.value # [1] 0.3917553 -- Peter Dalgaard Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ R-help@r-project.org 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.
