Hi all, thanks very much for sharing your thoughts. and sorry for my describing the problem not clearly, my fault.
My data is paired, that is 2 different diagnostic tests were performed on the same individuals. Each individual will have a test results from each of the 2 tests. Then in the end, 2 accuracy rates were calculated for the 2 tests. And I want to test if there is a significant difference in the accuracy (proportion) between the 2 tests. My understanding is that prop.test() is appropriate for 2 independent proportions, whereas in my situation, the 2 proportions are not independent calculated from "paired" data, right? the data would look like: pid test1 test2 p1 1 0 p2 1 1 p3 0 1 : : 1=test is correct; 0=not correct from the data above, we can calculate accuracy for test1 and test2, then to compare.... So mcnemar.test() is good for that, right? Thanks John ----- Original Message ----- From: Viechtbauer Wolfgang (STAT) <wolfgang.viechtba...@maastrichtuniversity.nl> To: "r-help@r-project.org" <r-help@r-project.org> Cc: Bert Gunter <gunter.ber...@gene.com> Sent: Wednesday, September 7, 2011 8:14 AM Subject: Re: [R] suggestion for proportions Indeed, the original post leaves some room for interpretation. In any case, I hope the OP has enough information now to figure out what approach is best for his data. Best, Wolfgang > -----Original Message----- > From: Bert Gunter [mailto:gunter.ber...@gene.com] > Sent: Wednesday, September 07, 2011 16:47 > To: Viechtbauer Wolfgang (STAT) > Cc: r-help@r-project.org; John Sorkin > Subject: Re: [R] suggestion for proportions > > Wolfgang: > > On Wed, Sep 7, 2011 at 7:28 AM, Viechtbauer Wolfgang (STAT) > <wolfgang.viechtba...@maastrichtuniversity.nl> wrote: > > Acutally, > > > > ?mcnemar.test > > > > since it is paired data. > > Actually, it is unclear to me from the OP's message whether this is the > case. > > In one sentence the OP says that the _number_ of samples is the same, > and in the next he says that "essentially" the samples are the same. > So, as usual, imprecision in the problem description leads to > imprecision in the solution. > > But your point is well taken, of course. > > -- Bert ______________________________________________ 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. ______________________________________________ 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.
