From: Peter Dalgaard <p.dalgaard_at_biostat.ku.dk>

Date: Thu 01 Dec 2005 - 03:02:12 EST

Date: Thu 01 Dec 2005 - 03:02:12 EST

Scott Story <sstory@montana.edu> writes:

> I am trying to write a function that will solve a simple system of

*> nonlinear equations for the parameters that describe the beta
**> distribution (a,b) given the mean and variance.
**>
**>
**> mean = a/(a+b)
**> variance = (a*b)/(((a+b)^2) * (a+b+1))
**>
**> Any help as to where to start would be welcome.
*

On a pad of paper...

First look at mean*(1-mean)/variance, and the rest should follow. (Hint minimized in case this was homework...)

-- O__ ---- Peter Dalgaard ุster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard@biostat.ku.dk) FAX: (+45) 35327907 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.htmlReceived on Thu Dec 01 04:03:21 2005

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