{ "id": "0909.3335", "version": "v1", "published": "2009-09-17T22:36:25.000Z", "updated": "2009-09-17T22:36:25.000Z", "title": "Efficient calculation of risk measures by importance sampling -- the heavy tailed case", "authors": [ "Henrik Hult", "Jens Svensson" ], "categories": [ "math.PR" ], "abstract": "Computation of extreme quantiles and tail-based risk measures using standard Monte Carlo simulation can be inefficient. A method to speed up computations is provided by importance sampling. We show that importance sampling algorithms, designed for efficient tail probability estimation, can significantly improve Monte Carlo estimators of tail-based risk measures. In the heavy-tailed setting, when the random variable of interest has a regularly varying distribution, we provide sufficient conditions for the asymptotic relative error of importance sampling estimators of risk measures, such as Value-at-Risk and expected shortfall, to be small. The results are illustrated by some numerical examples.", "revisions": [ { "version": "v1", "updated": "2009-09-17T22:36:25.000Z" } ], "analyses": { "subjects": [ "60C05", "60F05" ], "keywords": [ "importance sampling", "heavy tailed case", "efficient calculation", "tail-based risk measures", "standard monte carlo simulation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0909.3335H" } } }