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arXiv · 1202.6678

Calculating principal eigen-functions of non-negative integral kernels: particle approximations and applications

Abstract

Often in applications such as rare events estimation or optimal control it is required that one calculates the principal eigen-function and eigen-value of a non-negative integral kernel. Except in the finite-dimensional case, usually neither the principal eigen-function nor the eigen-value can be computed exactly. In this paper, we develop numerical approximations for these quantities. We show how a generic interacting particle algorithm can be used to deliver numerical approximations of the eigen-quantities and the associated so-called "twisted" Markov kernel as well as how these approximations are relevant to the aforementioned applications. In addition, we study a collection of random integral operators underlying the algorithm, address some of their mean and path-wise properties, and obtain $L_{r}$ error estimates. Finally, numerical examples are provided in the context of importance sampling for computing tail probabilities of Markov chains and computing value functions for a class of stochastic optimal control problems.

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BibTeXRIS

Nick Whiteley, Nikolas Kantas. 2012-02-29. Calculating principal eigen-functions of non-negative integral kernels: particle approximations and applications. https://arxiv.org/abs/1202.6678

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