On Sat, Mar 21, 2009 at 2:03 PM, joker77 <vijumo...@gmail.com> wrote: > > Hi, I noted a discrepancy between R and openepi when I ran a fisher test with > the same matrix. In R: > >> a=matrix(c(1,2,6,17), nrow=2) >> a > [,1] [,2] > [1,] 1 6 > [2,] 2 17 >> fisher.test(a, conf.int=T) > > Fisher's Exact Test for Count Data > > data: a > p-value = 1 > alternative hypothesis: true odds ratio is not equal to 1 > 95 percent confidence interval: > 0.02061498 31.73691924 > sample estimates: > odds ratio > 1.396646 > > But in openepi the P value is 1.25. (In another instance too for other sets > of data, I had got a p value of 1 in 3 instances for a prop.test when I got > 3 other answers on a friend's stata software with the same data. )
Given that a p-value is between 0 and 1, I would rather think that openEpi's accuracy is in doubt. Hadley -- http://had.co.nz/ ______________________________________________ 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.