Try thinking this one through from first principles, you are essentially saying that your null hypothesis is that you are flipping a fair coin and you want to do a 2-tailed test. You then flip the coin exactly once, what do you expect to happen? The p-value of 1 just means that what you saw was perfectly consistent with what is predicted to happen flipping a single time.
Does that help? If not, please explain what you mean a little better. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111 > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of Kay Cichini > Sent: Wednesday, September 01, 2010 3:06 PM > To: r-help@r-project.org > Subject: [R] general question on binomial test / sign test > > > hello, > > i did several binomial tests and noticed for one sparse dataset that > binom.test(1,1,0.5) gives a p-value of 1 for the null, what i can't > quite > grasp. that would say that the a prob of 1/2 has p-value of 0 ?? - i > must be > wrong but can't figure out the right interpretation.. > > best, > kay > > > > > > ----- > ------------------------ > Kay Cichini > Postgraduate student > Institute of Botany > Univ. of Innsbruck > ------------------------ > > -- > View this message in context: http://r.789695.n4.nabble.com/general- > question-on-binomial-test-sign-test-tp2419965p2419965.html > Sent from the R help mailing list archive at Nabble.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. ______________________________________________ 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.
