Volume no :2, Issue no: 1, September (2009)

IDENTIFIABILITY PROBLEMS RELATED WITH CREDIBILITY: A SURVEY WITH APPLICATIONS

Author's: Emilio Gómez-Déniz and Enrique Calderín-Ojeda
Pages: [53] - [70]
Received Date: August 26, 2009
Submitted by:

Abstract

Premium computation in a Bayesian context requires the use of a prior distribution that the unknown risk parameter of the likelihood follows in the heterogeneous population. Sometimes, the Bayes premium is expressed as a weighted sum of the sample mean and the collective premium, known in the literature as credibility formula.

In this paper, some connections between credibility theory and identifiability problems are reviewed and modestly extended by identifying the prior distribution under different likelihoods by the form of the Bayes premium, which results under appropriate likelihood and prior distribution a credibility formula. Results under the net premium principle for Poisson, binomial, and negative binomial likelihood functions and under the Esscher premium principle for Poisson likelihood function are shown. The methodology is applied to generate a wide spectrum of discrete distributions when non-credibility formulae appear.

Keywords

Bayes, credibility, discrete distributions, identification.