you should use the 'lower.tail' argument of pnorm(), e.g., check the following:
2 * (1 - pnorm(8.104474)) 2 * pnorm(8.104474, lower.tail = FALSE) I hope it helps. Best, Dimitris ---- Dimitris Rizopoulos Ph.D. Student Biostatistical Centre School of Public Health Catholic University of Leuven Address: Kapucijnenvoer 35, Leuven, Belgium Tel: +32/(0)16/336899 Fax: +32/(0)16/337015 Web: http://med.kuleuven.be/biostat/ http://www.student.kuleuven.be/~m0390867/dimitris.htm ----- Original Message ----- From: "jing hua zhao" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, February 07, 2008 6:00 PM Subject: [Rd] pnorm > > Dear R list, > > I calculated a two-sided p values according to > 2*(1-pnorm(8.104474)), which gives 4.440892e-16. However, it > appears to be 5.30E-16 by a colleague and 5.2974E-16 from SAS. I > tried to get around with mvtnorm package but it turns out to be > using pnorm for univariate case. I should have missed some earlier > discussions, but for the moment is there any short answer for a > higher precision? Somehow these days, statistical geneticists are > infatuated with such tiny p values! > > Many thanks in advance, > > > Jing Hua > > _________________________________________________________________ > Telly addicts unite! > > [[alternative HTML version deleted]] > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
