I think I should have posted this question here as well. I am posting my question here since it is R related. Please see below. I originally posted this to sci.stat.math
"Nasser Abbasi" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > > I think R documentation is a bit hard for me to sort out at this time. > > I was wondering if someone who knows R better than I do could please let > me know the command syntax to find the mean of Beta Negative Binomial > Distribution for the following parameters: > > n=3 > alpha=0.5 > beta=3 > > Here is the documenation page for R which mentions this distribution > > http://rweb.stat.umn.edu/R/library/SuppDists/html/ghyper.html > > Using Mathematica, I get (-18) for the mean and -150 for the variance, > and wanted to verify this with R, since there is a negative sign which is > confusing me. > > Mathematica says the formula for the mean is n*beta/(alpha-1) and that > is why the negative sign comes up. > alpha, beta, n can be any positive real numbers. > > If someone can just show me the R command for this, that will help, I have > the R package SuppDists installed, I am just not sure how to use it for > this distribution. > > thanks, > Nasser > I thought I should show what I did, this is R 2.6.1: tghyper(a=-1, k=-1, N=5) %I think this makes it do Beta Negative Binomail and now I used summary command, right? sghyper(3, .5, 3) But I do not think this is correct.Tried few other permitations. Hard for me to see how to set the parameters correctly for this distribution. thanks, Nasser ______________________________________________ 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.
