asa189, a FORTRAN90 code which does a maximum likelihood estimation of the parameters of a Beta Binomial Probability Density Function (PDF), by D Smith.

The code is Applied Statistics Algorithm 189.

This algorithm analyzes data that was generated by a beta binomial probability density function, and tries to estimate the values of the parameters that determing that PDF.


The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.


asa189 is available in a FORTRAN90 version.

Related Data and Programs:



Original FORTRAN77 version by D Smith; FORTRAN90 version by John Burkardt.


  1. D Smith,
    Algorithm AS 189: Maximum Likelihood Estimation of the Parameters of the Beta Binomial Distribution,
    Applied Statistics,
    Volume 32, Number 2, 1983, pages 196-204.

Source Code:

Last revised on 20 May 2020.