[R] How to fit a random data into Beta distribution?

[David Winsemius]

On May 11, 2011, at 11:17 PM, MikeK wrote:

> I am also trying to fit data to a beta distribution.
>
> In Ang and Tang, Probability Concepts in Engineering, 2nd Ed., page  
> 127-9,
> they describe a variant of a beta distribution with additional  
> parameters
> than the standard beta distribution, enabling specification of a max  
> and min
> value other than 0,1. This would be very useful for my purposes.
>
> Any thoughts on how to fit a distribution directly to this variant  
> of the
> beta distribution, without starting from scratch?
>

Scale your data to [0,1], fit, predict, invert the scaling.

xscaled <- (x-min(x))/max(x)
....
xrescaled <- max(x)*xscaled + min(x)

(Better check that I made the correct order of those operations. The  
first attempt was wrong ... I think.)

-- 
David Winsemius, MD
West Hartford, CT