Imperial College London
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ProfessorDanCrisan

Faculty of Natural Sciences, Department of Mathematics

Professor of Mathematics
 
 
 
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Contact

 

+44 (0)20 7594 8489d.crisan Website

 
 
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Location

 

670Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Crisan:2014:10.3150/13-BEJ545,
author = {Crisan, D and Míguez, J},
doi = {10.3150/13-BEJ545},
journal = {Bernoulli},
pages = {1879--1929},
title = {Particle-kernel estimation of the filter density in state-space models},
url = {http://dx.doi.org/10.3150/13-BEJ545},
volume = {20},
year = {2014}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Sequential Monte Carlo (SMC) methods, also known as particle filters, are simulation-based recursive algorithms for the approximation of the a posteriori probability measures generated by state-space dynamical models. At any given time t, a SMC method produces a set of samples over the state space of the system of interest (often termed "particles") that is used to build a discrete and random approximation of the posterior probability distribution of the state variables, conditional on a sequence of available observations. One potential application of the methodology is the estimation of the densities associated to the sequence of a posteriori distributions. While practitioners have rather freely applied such density approximations in the past, the issue has received less attention from a theoretical perspective. In this paper, we address the problem of constructing kernel-based estimates of the posterior probability density function and its derivatives, and obtain asymptotic convergence results for the estimation errors. In particular, we find convergence rates for the approximation errors that hold uniformly on the state space and guarantee that the error vanishes almost surely as the number of particles in the filter grows. Based on this uniform convergence result, we first show how to build continuous measures that converge almost surely (with known rate) toward the posterior measure and then address a few applications. The latter include maximum a posteriori estimation of the system state using the approximate derivatives of the posterior density and the approximation of functionals of it, for example, Shannon's entropy.
AU  - Crisan,D
AU  - Míguez,J
DO  - 10.3150/13-BEJ545
EP  - 1929
PY  - 2014///
SN  - 1350-7265
SP  - 1879
TI  - Particle-kernel estimation of the filter density in state-space models
T2  - Bernoulli
UR  - http://dx.doi.org/10.3150/13-BEJ545
VL  - 20
ER  -
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