Importance Sampling for multi-constraints rare event probability

Virgile Caron

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arXiv · 1401.3257

Importance Sampling for multi-constraints rare event probability

Virgile Caron

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Abstract

Improving Importance Sampling estimators for rare event probabilities requires sharp approx- imations of the optimal density leading to a nearly zero-variance estimator. This paper presents a new way to handle the estimation of the probability of a rare event defined as a finite intersection of subset. We provide a sharp approximation of the density of long runs of a random walk condi- tioned by multiples constraints, each of them defined by an average of a function of its summands as their number tends to infinity.

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Virgile Caron. 2014-01-14. Importance Sampling for multi-constraints rare event probability. https://arxiv.org/abs/1401.3257

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