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Concentration bounds for empirical conditional value-at-risk: the unbounded case. (English) Zbl 1476.91220

Summary: Conditional Value-at-Risk (CVaR) is a popular risk measure for modelling losses in the case of a rare but extreme event. We consider the problem of estimating CVaR from i.i.d. samples of an unbounded random variable, which is either sub-Gaussian or sub-exponential. We derive a novel one-sided concentration bound for a natural sample-based CVaR estimator in this setting. Our bound relies on a concentration result for a quantile-based estimator for Value-at-Risk (VaR), which may be of independent interest.

MSC:

91G70 Statistical methods; risk measures

References:

[1] Bardou, O.; Frikha, N.; Pages, G., Computing VaR and CVaR using stochastic approximation and adaptive unconstrained importance sampling, Monte Carlo Methods Appl., 15, 3, 173-210 (2009) · Zbl 1185.91091
[2] Boucheron, S.; Lugosi, G.; Massart, P., Concentration Inequalities: A Nonasymptotic Theory of Independence (2013), Oxford University Press · Zbl 1279.60005
[3] Brown, D. B., Large deviations bounds for estimating conditional value-at-risk, Oper. Res. Lett., 35, 6, 722-730 (2007) · Zbl 1189.91069
[4] Bubeck, S.; Cesa-Bianchi, N., Regret analysis of stochastic and nonstochastic multi-armed bandit problems, Found. Trends Mach. Learn., 5, 1, 1-122 (2012) · Zbl 1281.91051
[5] J. Kisiala, Conditional value-at-risk: Theory and applications, 2015, arXiv preprint arXiv:1511.00140; J. Kisiala, Conditional value-at-risk: Theory and applications, 2015, arXiv preprint arXiv:1511.00140
[6] Krokhmal, P.; Zabarankin, M.; Uryasev, S., Modeling and optimization of risk, Surv. Oper. Res. Manag. Sci., 16, 49-66 (2011)
[7] Robbins, H., Some aspects of the sequential design of experiments, (Bulletin of the American Mathematical Society, vol. 55 (1952)) · Zbl 0049.37009
[8] Serfling, R. J., Approximation Theorems of Mathematical Statistics, Vol. 162 (2009), John Wiley & Sons
[9] Sun, L.; Hong, L. J., Asymptotic representations for importance-sampling estimators of value-at-risk and conditional value-at-risk, Oper. Res. Lett., 38, 4, 246-251 (2010) · Zbl 1193.91165
[10] Wang, Y.; Gao, F., Deviation inequalities for an estimator of the conditional value-at-risk, Oper. Res. Lett., 38, 3, 236-239 (2010) · Zbl 1189.91085
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