[R] Solving Systems of Non-linear equations

[Peter Dalgaard]

Scott Story <sstory at 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...)

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