Quantile estimation in the two-parameter gamma distribution

The gamma distribution is applicable in situations where intervals between events
are considered as well as where a skewed distribution is appropriate. Estimation
of parameters is revisited in the two-parameter gamma distribution. The method
of quantile estimates is implemented to this distribution. A comparative study
between the method of moments, the maximum likelihood method, the method of
product spacings, and the method of quantile estimates is performed using simulation.
For the scale parameter, the maximum likelihood estimate performs better
and for the shape parameter, the product spacings estimate performs better.