Title
Probabilistic Variational Bounds for Graphical Models
Abstract
Variational algorithms such as tree-reweighted belief propagation can provide deterministic bounds on the partition function, but are often loose and difficult to use in an \"any-time\" fashion, expending more computation for tighter bounds. On the other hand, Monte Carlo estimators such as importance sampling have excellent any-time behavior, but depend critically on the proposal distribution. We propose a simple Monte Carlo based inference method that augments convex variational bounds by adding importance sampling (IS). We argue that convex variational methods naturally provide good IS proposals that \"cover\" the target probability, and reinterpret the variational optimization as designing a proposal to minimize an upper bound on the variance of our IS estimator. This both provides an accurate estimator and enables construction of any-time probabilistic bounds that improve quickly and directly on state-of-the-art variational bounds, and provide certificates of accuracy given enough samples relative to the error in the initial bound.
Year
Venue
Field
2015
Annual Conference on Neural Information Processing Systems
Mathematical optimization,Importance sampling,Monte Carlo method,Computer science,Upper and lower bounds,Graphical model,Probabilistic logic,Estimator,Computation,Belief propagation
DocType
Volume
ISSN
Conference
28
1049-5258
Citations 
PageRank 
References 
1
0.36
17
Authors
3
Name
Order
Citations
PageRank
Liu, Qiang147248.61
John W. Fisher III287874.44
Alexander T. Ihler31377112.01