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arXiv · 1902.08582

A Family of Bayesian Cram\'er-Rao Bounds, and Consequences for Log-Concave Priors

Efe Aras·Kuan-Yun Lee·Ashwin Pananjady·Thomas A. Courtade
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Abstract

Under minimal regularity assumptions, we establish a family of information-theoretic Bayesian Cram\'er-Rao bounds, indexed by probability measures that satisfy a logarithmic Sobolev inequality. This family includes as a special case the known Bayesian Cram\'er-Rao bound (or van Trees inequality), and its less widely known entropic improvement due to Efroimovich. For the setting of a log-concave prior, we obtain a Bayesian Cram\'er-Rao bound which holds for any (possibly biased) estimator and, unlike the van Trees inequality, does not depend on the Fisher information of the prior.

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Efe Aras, Kuan-Yun Lee, Ashwin Pananjady, Thomas A. Courtade. 2019-02-22. A Family of Bayesian Cram\'er-Rao Bounds, and Consequences for Log-Concave Priors. https://arxiv.org/abs/1902.08582

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