Title
Markov Chain Monte Carlo Inference of Parametric Dictionaries for Sparse Bayesian Approximations.
Abstract
Parametric dictionaries can increase the ability of sparse representations to meaningfully capture and interpret the underlying signal information, such as encountered in biomedical problems. Given a mapping function from the atom parameter space to the actual atoms, we propose a sparse Bayesian framework for learning the atom parameters, because of its ability to provide full posterior estimates, take uncertainty into account and generalize on unseen data. Inference is performed with Markov Chain Monte Carlo, that uses block sampling to generate the variables of the Bayesian problem. Since the parameterization of dictionary atoms results in posteriors that cannot be analytically computed, we use a Metropolis-Hastings-within-Gibbs framework, according to which variables with closed-form posteriors are generated with the Gibbs sampler, while the remaining ones with the Metropolis Hastings from appropriate candidate-generating densities. We further show that the corresponding Markov Chain is uniformly ergodic ensuring its convergence to a stationary distribution independently of the initial state. Results on synthetic data and real biomedical signals indicate that our approach offers advantages in terms of signal reconstruction compared to previously proposed Steepest Descent and Equiangular Tight Frame methods. This paper demonstrates the ability of Bayesian learning to generate parametric dictionaries that can reliably represent the exemplar data and provides the foundation towards inferring the entire variable set of the sparse approximation problem for signal denoising, adaptation and other applications.
Year
DOI
Venue
2016
10.1109/TSP.2016.2539143
IEEE Trans. Signal Processing
Keywords
Field
DocType
Dictionary learning,bayesian inference,markov chain monte carlo,parametric dictionaries,sparse representation,uniform ergodicity
Rejection sampling,Bayesian inference,Metropolis–Hastings algorithm,Markov chain Monte Carlo,Particle filter,Artificial intelligence,Gibbs sampling,Mathematical optimization,Pattern recognition,Markov chain,Sparse approximation,Algorithm,Mathematics
Journal
Volume
Issue
ISSN
64
12
1053-587X
Citations 
PageRank 
References 
2
0.43
28
Authors
4
Name
Order
Citations
PageRank
Theodora Chaspari13819.43
Andreas Tsiartas2518.46
Panagiotis Tsilifis381.66
Narayanan Shrikanth45558439.23