Shrinkage estimation of reliability in the exponential distribution

In this paper we propose two shrinkage testimators for the reliability of the exponential distribution and study their properties. The optimum shrinkage coefficients for the shrinkage testimators are obtained based on a regret function and the minimax regret criterion. Shrinkage testimators are compared with a preliminary test estimator and with the usual estimator in terms of mean squared error. The proposed shrinkage testimators are shown to be preferable to the preliminary test estimator and the usual estimator when the prior value of mean life is close to the true mean life.