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arXiv · 1903.12299

Large Deviations of Factor Models with Regularly-Varying Tails: Asymptotics and Efficient Estimation

Farzad Pourbabaee·Omid Shams Solari
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Abstract

We analyze the \textit{Large Deviation Probability (LDP)} of linear factor models generated from non-identically distributed components with \textit{regularly-varying} tails, a large subclass of heavy tailed distributions. An efficient sampling method for LDP estimation of this class is introduced and theoretically shown to exponentially outperform the crude Monte-Carlo estimator, in terms of the coverage probability and the confidence interval's length. The theoretical results are empirically validated through stochastic simulations on independent non-identically Pareto distributed factors. The proposed estimator is available as part of a more comprehensive \texttt{Betta} package.

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Farzad Pourbabaee, Omid Shams Solari. 2019-03-28. Large Deviations of Factor Models with Regularly-Varying Tails: Asymptotics and Efficient Estimation. https://arxiv.org/abs/1903.12299

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