Title
Adaptive MCMC with online relabeling
Abstract
When targeting a distribution that is artificially invariant under some permutations, Markov chain Monte Carlo (MCMC) algorithms face the label-switching problem, rendering marginal inference particularly cumbersome. Such a situation arises, for example, in the Bayesian analysis of finite mixture models. Adaptive MCMC algorithms such as adaptive Metropolis (AM), which self-calibrates its proposal distribution using an online estimate of the covariance matrix of the target, are no exception. To address the label-switching issue, relabeling algorithms associate a permutation to each MCMC sample, trying to obtain reasonable marginals. In the case of adaptive Metropolis (Bernoulli 7 (2001) 223-242), an online relabeling strategy is required. This paper is devoted to the AMOR algorithm, a provably consistent variant of AM that can cope with the label-switching problem. The idea is to nest relabeling steps within the MCMC algorithm based on the estimation of a single covariance matrix that is used both for adapting the covariance of the proposal distribution in the Metropolis algorithm step and for online relabeling. We compare the behavior of AMOR to similar relabeling methods. In the case of compactly supported target distributions, we prove a strong law of large numbers for AMOR and its ergodicity. These are the first results on the consistency of an online relabeling algorithm to our knowledge. The proof underlines latent relations between relabeling and vector quantization.
Year
DOI
Venue
2012
10.3150/13-BEJ578
BERNOULLI
Keywords
Field
DocType
adaptive Markov chain Monte Carlo,label-switching,stochastic approximation,vector quantization
Lyapunov function,Mathematical optimization,Markov chain Monte Carlo,Inference,Computer science,Vector quantization,Label switching,Artificial intelligence,Stochastic approximation,Mixture model,Machine learning,Bayesian probability
Journal
Volume
Issue
ISSN
21
3
1350-7265
Citations 
PageRank 
References 
0
0.34
2
Authors
4
Name
Order
Citations
PageRank
Rémi Bardenet135016.90
O. Cappe22112207.95
Gersende Fort315016.59
Balázs Kégl497367.08