The Annals of Applied Probability
- Ann. Appl. Probab.
- Volume 22, Number 4 (2012), 1495-1540.
Ergodicity and stability of the conditional distributions of nondegenerate Markov chains
Xin Thomson Tong and Ramon van Handel
Abstract
We consider a bivariate stationary Markov chain $(X_{n},Y_{n})_{n\ge0}$ in a Polish state space, where only the process $(Y_{n})_{n\ge0}$ is presumed to be observable. The goal of this paper is to investigate the ergodic theory and stability properties of the measure-valued process $(\Pi_{n})_{n\ge0}$, where $\Pi_{n}$ is the conditional distribution of $X_{n}$ given $Y_{0},\ldots,Y_{n}$. We show that the ergodic and stability properties of $(\Pi_{n})_{n\ge0}$ are inherited from the ergodicity of the unobserved process $(X_{n})_{n\ge0}$ provided that the Markov chain $(X_{n},Y_{n})_{n\ge0}$ is nondegenerate, that is, its transition kernel is equivalent to the product of independent transition kernels. Our main results generalize, subsume and in some cases correct previous results on the ergodic theory of nonlinear filters.
Article information
Source
Ann. Appl. Probab., Volume 22, Number 4 (2012), 1495-1540.
Dates
First available in Project Euclid: 10 August 2012
Permanent link to this document
https://projecteuclid.org/euclid.aoap/1344614202
Digital Object Identifier
doi:10.1214/11-AAP800
Mathematical Reviews number (MathSciNet)
MR2985168
Zentralblatt MATH identifier
1252.60069
Subjects
Primary: 60J05: Discrete-time Markov processes on general state spaces 28D99: None of the above, but in this section
Secondary: 62M20: Prediction [See also 60G25]; filtering [See also 60G35, 93E10, 93E11] 93E11: Filtering [See also 60G35] 93E15: Stochastic stability
Keywords
Nonlinear filtering unique ergodicity asymptotic stability nondegenerate Markov chains exchange of intersection and supremum Markov chain in random environment
Citation
Tong, Xin Thomson; van Handel, Ramon. Ergodicity and stability of the conditional distributions of nondegenerate Markov chains. Ann. Appl. Probab. 22 (2012), no. 4, 1495--1540. doi:10.1214/11-AAP800. https://projecteuclid.org/euclid.aoap/1344614202