Value of the beta prior information

Abstract

Information gain or loss is studied here by considering changes in the reciprocal of the expected posterior variance. For two beta distributions, the ratio of the expected values of their posterior variances provides a convenient criterion which is consistent with several results of the bayesian set-up and also permits the determination of the least informative prior beta distribution. Relations with results obtained by other authors are also discussed.

Keywords:

• information ratio
• posterior variance
• least informative prior
• beta distribution
• bounds