Estimation of alpha and beta parameters for prior Beta distributions
This utility calculates the alpha and beta parameters for prior Beta distributions,
based on the values specified for the mode and 5th or 95th percentile of the distribution.
Required input are both mode and 5/95th percentile for the desired distribution. Values must
be >0 and <1. It is suggested that, where the mode is less than 0.5, you enter the 95th percentile,
and where the mode is greater than 0.5 enter the 5th percentile.
Outputs are the alpha and beta parameters and a density curve for the distribution.