Just run a t-test. See: ?t.test Dimitri
On Wed, May 5, 2010 at 3:54 PM, Dmitry Gospodaryov <gospodar...@rambler.ru>wrote: > Dear developers of R-project, > I have such data > height of male persons > 181, 178, 182, 160, 187, 193, 184, 184, > 175, 178, 184, 184, 174, 185, 175 > height of female persons > 164, 165, 160, 174, 167, 161, 164, 165, > 169, 175, 165, 155, 172, 164, 172, 166, > 160, 159, 158, 173 > I want to determine if height is dependent on > gender, and I need to find, as I understand, point > biserial correlation. I had tried to use package "ltm", > and obtained coefficient which is about 0.74. I also > had tried to calculate it manually (with some MS Excel help > for simple calculations), using equation given in Internet > (e.g., in Wikipedia; this equation is also given in some > copy-books) and obtained coefficient is about 0.77. > "ltm" provides somewhat other equation with pi-numbers. > So, the questions are following: > 1). Do exist packages in R-project, except of "polycor" and > "ltm", which provide calculation of point biserial correlation? > 1a). Why "ltm" use "non-traditional" equation for > bisserial coefficient? Which is significance of this difference? > 2). Can I also calculate significance of the biserial correlation > coefficient (p < ???; using, probably, t-test) by means of > R-project? > > Thank You for advance. > With regard, > Dmitry Gospodaryov. > > ______________________________________________ > 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. > -- Dimitri Liakhovitski Ninah.com dimitri.liakhovit...@ninah.com [[alternative HTML version deleted]] ______________________________________________ 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.
