- Bayesian Anal.
- Volume 14, Number 1 (2019), 235-260.
On Bayesian Oracle Properties
When model uncertainty is handled by Bayesian model averaging (BMA) or Bayesian model selection (BMS), the posterior distribution possesses a desirable “oracle property” for parametric inference, if for large enough data it is nearly as good as the oracle posterior, obtained by assuming unrealistically that the true model is known and only the true model is used. We study the oracle properties in a very general context of quasi-posterior, which can accommodate non-regular models with cubic root asymptotics and partial identification. Our approach for proving the oracle properties is based on a unified treatment that bounds the posterior probability of model mis-selection. This theoretical framework can be of interest to Bayesian statisticians who would like to theoretically justify their new model selection or model averaging methods in addition to empirical results. Furthermore, for non-regular models, we obtain nontrivial conclusions on the choice of prior penalty on model complexity, the temperature parameter of the quasi-posterior, and the advantage of BMA over BMS.
Bayesian Anal., Volume 14, Number 1 (2019), 235-260.
First available in Project Euclid: 16 May 2018
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Digital Object Identifier
Jiang, Wenxin; Li, Cheng. On Bayesian Oracle Properties. Bayesian Anal. 14 (2019), no. 1, 235--260. doi:10.1214/18-BA1097. https://projecteuclid.org/euclid.ba/1526457619
- Supplement to “On Bayesian Oracle Properties”. We provide the technical proofs of Theorem 3, Theorem 4, and Corollary 1, as well as additional discussion on the Bayesian oracle properties for partial identification.