Hi Ivo, Try something like this:
rt(1e5, df = 2.6, ncp = (1 - 0) * sqrt(2.6 + 1)/2) The NCP comes from the mean, N, and SD. See ?rt Cheers, Josh On Fri, Mar 15, 2013 at 6:58 PM, ivo welch <ivo.we...@anderson.ucla.edu> wrote: > dear R experts: > > fitdistr suggests that a t with a mean of 1, an sd of 2, and 2.6 > degrees of freedom is a good fit for my data. > > now I want to draw random samples from this distribution. should I > draw from a uniform distribution and use the distribution function > itself for the transform, or is there a better way to do this? there > is a non-centrality parameter ncp in rt, but one parameter ncp cannot > subsume two (m and s), of course. my first attempt was to draw > rt(..., df=2.63)*s+m, but this was obviously not it. > > advice appreciated. > > /iaw > > ---- > Ivo Welch (ivo.we...@gmail.com) > http://www.ivo-welch.info/ > > ______________________________________________ > 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. -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles http://joshuawiley.com/ Senior Analyst - Elkhart Group Ltd. http://elkhartgroup.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.
