Marc Schwartz <marc_schwa...@me.com> [Tue, Dec 28, 2010 at 06:30:59PM CET]: > > On Dec 28, 2010, at 11:05 AM, Manoj Aravind wrote: > > > Hi friends, > > I get different values for McNemar's test in R and SPSS. Which one should i > > rely on when the p values differ.
[...] > > > The SPSS test appears to be an exact test, whereas the default R function > does not perform an exact test, so you are not comparing Apples to Apples... > Indeed, binom.test(11, 14) renders the same p-value as SPSS, whereas mcnemar.test() uses the approximation (|a_12 - a_21| - 1)²/(a_21 + a_12) with the "-1" removed if correct=FALSE. An old question of mine: Is there any reason not to use binom.test() other than historical reasons? -- Johannes Hüsing There is something fascinating about science. One gets such wholesale returns of conjecture mailto:johan...@huesing.name from such a trifling investment of fact. http://derwisch.wikidot.com (Mark Twain, "Life on the Mississippi") ______________________________________________ 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.