hypergeometric
The hypergeo package should be able to deal with this, although the function you specify below looks like a degenerate case (if I understand it correctly) so the convergence rate is likely to be slow. Let me know how you get on best wishes Robin (author of hypergeo)
Jarle Brinchmann wrote:
The dhyper etc deal with the hypergeometric _distribution_ while what
you appear to want have is the hypergeometric special function (the
connection is that the regular hypergeometric function is the
generating function for the hypergeometric distribution if I recall
correctly).
Anyway, what you need, I believe, is the hypergeo library from CRAN.
Cheers,
Jarle.
On Wed, Dec 3, 2008 at 9:17 AM, Zakaria, Roslinazairimah - zakry001
<Roslinazairimah.Zakaria at postgrads.unisa.edu.au> wrote:
Hi,
I hope somebody can help me on how to use the hypergeometric function.
I did read through the R documentation on hypergeometric but not really
sure what it means.
I would like to evaluate the hypergeometric function as follows:
F((2*alpha+1)/2, (2*alpha+2)/2 , alpha+1/2, betasq/etasq).
I'm not sure which function should be used- either phyper or qhyper or
dhyper
Where
alpha <- .75; beta1 <- 7 ; beta2 <- 5.5;
etasq <- ((beta1+beta2)/(2*beta1*beta2*(1-rho))) ^2
betasq <-
((beta1-beta2)^2+4*beta1*beta2*rho)/(4*beta1^2*beta2^2*(1-rho)^2)
Thank you so much for your help.
Robin K. S. Hankin Uncertainty Analyst University of Cambridge 19 Silver Street Cambridge CB3 9EP 01223-764877