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arXiv · 1706.02375

Fast Black-box Variational Inference through Stochastic Trust-Region Optimization

Abstract

We introduce TrustVI, a fast second-order algorithm for black-box variational inference based on trust-region optimization and the reparameterization trick. At each iteration, TrustVI proposes and assesses a step based on minibatches of draws from the variational distribution. The algorithm provably converges to a stationary point. We implemented TrustVI in the Stan framework and compared it to two alternatives: Automatic Differentiation Variational Inference (ADVI) and Hessian-free Stochastic Gradient Variational Inference (HFSGVI). The former is based on stochastic first-order optimization. The latter uses second-order information, but lacks convergence guarantees. TrustVI typically converged at least one order of magnitude faster than ADVI, demonstrating the value of stochastic second-order information. TrustVI often found substantially better variational distributions than HFSGVI, demonstrating that our convergence theory can matter in practice.

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BibTeXRIS

Jeffrey Regier, Michael I. Jordan, Jon McAuliffe. 2017-06-07. Fast Black-box Variational Inference through Stochastic Trust-Region Optimization. https://arxiv.org/abs/1706.02375

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