Abstract
In this paper, we deal with the estimation problem for the extreme value parameters in the case of stationary \(\beta\)-mixing serials with heavy-tailed distributions. We first introduce two families of estimators generalizing the Hill’s estimator. And from those families, three asymptotically unbiased estimators of the extreme value index are established. Our reflection is based on the generalized Jackknife methodology which consists of taking any pair of three special cases of our family of estimators to cancel the bias term. The resulting estimators are also used to deduce three asymptotically unbiased estimators of the extreme quantiles. In a simulation survey, the performance of our proposed methods are compared to alternative estimators recently introduced in the literature. Finally, our methods are applied to high financial losses data in order to estimate the Value-at-Risk of the daily stock returns on the S&P500 index.
REFERENCES
M. I. Fraga Alves, M. Ivette Gomes, and Laurens de Haan, ‘‘A new class of semiparametric estimators of the second order parameter,’’ Portugaliae Mathematica 60 (9), 193–214 (2003).
Jan Beirlant, G. Dierckx, Y. Goegebeur, and G. Matthys, ‘‘Tail index estimation and an exponential regression model,’’ Extremes 2 (2), 177–200 (1999).
Valérie Chavez-Demoulin and Armelle Guillou, ‘‘Extreme quantile estimation for \(\beta\)-mixing time series and applications,’’ Insurance: Mathematics and Economics 83 (16), 59–74 (2018).
Laurens De Haan, Cécile Mercadier, and Chen Zhou, ‘‘Adapting extreme value statistics to financial time series: dealing with bias and serial dependence,’’ Finance and Stochastics 20 (2), 321–354 (2016).
Arnold L. M. Dekkers, John H. J. Einmahl, and Laurens De Haan, ‘‘A moment estimator for the index of an extreme-value distribution,’’ The Annals of Statistics 17 (3), 1833–1855.
El Hadji Deme, Laurent Gardes, and Stéphane Girard, ‘‘On the estimation of the second order parameter for heavy-tailed distributions,’’ REVSTAT-Statistical Journal 11 (3), 277–299 (2013).
Holger Drees, ‘‘Extreme quantile estimation for dependent data, with applications to finance,’’ Bernoulli 9 (4), 617–657 (2003).
Holger Drees, ‘‘Weighted approximations of tail processes for \(\beta\)-mixing random variables,’’ The Annals of Applied Probability 10 (5), 1274–1301 (2000).
Holger Drees and Edgar Kaufmann, ‘‘Selecting the optimal sample fraction in univariate extreme value estimation,’’ Stochastic Processes and Their Applications 75 (7), 149–172 (1998).
Andrey Feuerverger and Peter Hall, ‘‘Estimating a tail exponent by modelling departure from a Pareto distribution,’’ The Annals of Statistics 27 (8), 760–781 (1999).
Yuri Goegebeur, Jan Beirlant, and Tertius de Wet, ‘‘Kernel estimators for the second order parameter in extreme value statistics,’’ Journal of statistical Planning and Inference 140 (10), 2632–2652 (2010).
M. Ivette Gomes and M João Martins, ‘‘‘Asymptotically unbiased’ estimators of the tail index based on external estimation of the second order parameter,’’ Extremes 5 (14), 5–31 (2002).
M. Ivette Gomes and M. João Martins, ‘‘Generalizations of the Hill estimator.asymptotic versus finite sample behaviour,’’ Journal of statistical planning and inference 93 (13), 161–180 (2001).
Bruce M. Hill, ‘‘A simple general approach to inference about the tail of a distribution,’’ In: The annals of statistics 3 (17), 1163–1174 (1975).
Tailen Hsing, ‘‘On tail index estimation using dependent data,’’ In: The Annals of Statistics 18, 1547–1569 (1991).
M. Ivette Gomes, Laurens De Haan, and Lıgia Henriques Rodrigues, ‘‘Tail index estimation for heavy-tailed models: Accommodation of bias in weighted log-excesses,’’ Journal of the Royal Statistical Society: Series B (Statistical Methodology) 70 (1), 31–52 (2008).
M. Ivette Gomes, M. João Martins, and Manuela Neves, ‘‘Alternatives to a semiparametric estimator of parameters of rare events.the Jackknife methodology,’’ Extremes 3 (12), 207–229 (2000).
Pavlina Jordanova, Z. Fabián, P. Hermann, et al., ‘‘Weak properties and robustness of t-Hill estimators,’’ Extremes 19 (19), 591–626 (2016).
Harry Kesten, ‘‘Random difference equations and renewal theory for products of random matrices,’’ 20 (1973).
Gunther Matthys, E. Delafosse, A. Guillou, and J. Beirlant, ‘‘Estimating catastrophic quantile levels for heavy-tailed distributions,’’ In: Insurance: Mathematics and Economics 34 (21), 517–537 (2004).
Alexander J. McNeil, Rüdiger Frey, and Paul Embrechts, Quantitative Risk Management: Concepts, Techniques and Tools-Revised Edition 22 (Princeton University Press, 2015).
L. Peng, ‘‘Asymptotically unbiased estimators for the extreme-value index,’’ Statistics and Probability Letters 38 (23), 107–115 (1998).
Rolf-Dieter Reiss and Michael Thomas, Statistical Analysis of Extreme Values. With Applications to Insurance, Finance, Hydrology, and Other Fields 24, 3rd ed. (Birkhäuser, 2007).
C Stărică, On the Tail Empirical Process of Solutions of Stochastic Difference Equations, Tech. Rep. 25 (Working Paper, Chalmers University, 2000), Vol. 22.
Daniel K. Tarullo, Banking on Basel: The Future of International Financial Regulation 26 (Peterson Institute, 2008).
Ishay Weissman, ‘‘Estimation of parameters and large quantiles based on the k largest observations,’’ Journal of the American Statistical Association 73 (27), 812–815 (1978).
JulienWorms and RymWorms, ‘‘Estimation of second order parameters using probability weighted moments,’’ ESAIM: Probability and Statistics 16 (28), 97–113 (2012).
ACKNOWLEDGMENTS
The authors would like to thank the Reviewers and editors for their valuable comments and suggestions that helped improve considerably the paper.
Author information
Authors and Affiliations
Corresponding author
About this article
Cite this article
Barry, M.A., Deme, E.H., Diop, A. et al. Improved Estimators of Tail Index and Extreme Quantiles under Dependence Serials. Math. Meth. Stat. 32, 133–153 (2023). https://doi.org/10.3103/S1066530723020011
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.3103/S1066530723020011