A new point estimator for the median of gamma distribution

In this paper, we consider the problem of estimating the median of a gamma distribution. We introduce a new point estimator based on an approximation that we derive for the median of a gamma distribution. We compare the new estimator with two conventional estimators, namely the sample median and the maximum likelihood estimator (mle). Comparison is based on the amount of computations required to calculate the estimates and the root mean square errors of the estimators. The new estimator is shown to be 'optimum' with respect to these two criteria.

Keywords and phrases: gamma distribution, median, point estimate, maximum likelihood estimate, moment estimate.

Vidyodaya J. of Sci.. (2009) Vol. 14, pp 95-103