[R] multivariate distributions

2010-08-27 Thread Rofizah Mohammad
Hi,

How can I generate data from multivariate gamma distribution  multivariate
beta distribution?
I only found command for multivariate normal only.
Many thanks in advance :)

Regards
Rofizah

[[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.


Re: [R] multivariate distributions

2010-08-27 Thread David Winsemius


On Aug 27, 2010, at 10:42 AM, Rofizah Mohammad wrote:


Hi,

How can I generate data from multivariate gamma distribution   
multivariate

beta distribution?
I only found command for multivariate normal only.


You need to improve your searching skills:

rhelpSearch
function(string,
 restrict = c(Rhelp10, Rhelp08, Rhelp02, functions ),
 matchesPerPage = 100, ...) {
RSiteSearch(string=string,
restrict = restrict,
matchesPerPage = matchesPerPage, ...)}

rhelpSearch(generate multivariate gamma)

Finds (after a small bit of web-clicking) this from  
Dimitris.Rizopoulos :


http://finzi.psych.upenn.edu/R/Rhelp02/archive/86491.html



Many thanks in advance :)

Regards
Rofizah


David Winsemius, MD
West Hartford, CT

__
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.


Re: [R] multivariate distributions

2010-08-27 Thread Dennis Murphy
Hi:

One form of a multivariate beta distribution is the Dirichlet, so using
package sos,

library(sos)   # install if necessary
u - findFn('Dirichlet distribution')
grepFn('Dirichlet distribution', u, column = 'Description', ignore.case =
TRUE)

reveals about 25 matches, about half of which lead somewhere useful. Of
course, there are several forms of the multivariate Beta so this may not be
what you need.

While Googling 'multivariate gamma' (a good idea, BTW, as there seem to be
several useful papers that might bear on this problem), I ran across the
following paper that may be of help:
http://smu.edu/statistics/TechReports/AbuRnpaper.pdf

They mention using S-PLUS functions to demonstrate simulations from
multivariate Beta and Gamma distributions, but don't show the code in the
paper. Perhaps you could contact the authors and see if you can gain access
to their code. Usually, S-PLUS code can be used in R. It's probable that you
will need to do some tweaking, but it appears that something is out there to
deal with the problem, at least...

HTH,
Dennis

On Fri, Aug 27, 2010 at 7:42 AM, Rofizah Mohammad rofi...@gmail.com wrote:

 Hi,

 How can I generate data from multivariate gamma distribution  multivariate
 beta distribution?
 I only found command for multivariate normal only.
 Many thanks in advance :)

 Regards
 Rofizah

[[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.


[[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.