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arXiv · 1909.12239

The $f$-Divergence Expectation Iteration Scheme

Kamélia Daudel·Randal Douc·François Portier·François Roueff
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Abstract

This paper introduces the $f$-EI$(\phi)$ algorithm, a novel iterative algorithm which operates on measures and performs $f$-divergence minimisation in a Bayesian framework. We prove that for a rich family of values of $(f,\phi)$ this algorithm leads at each step to a systematic decrease in the $f$-divergence and show that we achieve an optimum. In the particular case where we consider a weighted sum of Dirac measures and the $\alpha$-divergence, we obtain that the calculations involved in the $f$-EI$(\phi)$ algorithm simplify to gradient-based computations. Empirical results support the claim that the $f$-EI$(\phi)$ algorithm serves as a powerful tool to assist Variational methods.

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BibTeXRIS

Kamélia Daudel, Randal Douc, François Portier, François Roueff. 2019-09-26. The $f$-Divergence Expectation Iteration Scheme. https://arxiv.org/abs/1909.12239

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