A Pickands type estimator of the extreme value index (original) (raw)

On the comparison of several classical estimators of the extreme value index

Communications in Statistics - Theory and Methods, 2020

Due to the fact that for heavy tails the classical Hill estimator of a positive extreme value index is asymptotically biased, new and interesting alternative estimators have appeared in the literature. In this work we compare several classical estimators of the extreme value index based on moments of the upper order statistics. Since several alternative estimators have eventually a null asymptotic bias, for some heavy tailed models, the comparison is performed not only with the Hill and recent generalized means estimators but also with an asymptotically unbiased Hill estimator. The comparison study is performed asymptotically, under a third-order framework, and for finite samples, through a Monte Carlo simulation study.

On a consistent estimate of the index of an extreme value distribution

Siam Journal on Applied Mathematics - SIAMAM, 1987

An easy proof is given for the weak consistency of Pickands' estimate of the main parameter of an extreme-value distribution. Moreover further natural conditions are given for strong consistency and for asymptotic normality of the estimate.

Comparison of asymptotically unbiased extreme value index estimators: A Monte Carlo simulation study

2014

In this paper we are interested in the semi-parametric estimation of the extreme value index of a heavy-tailed model. We consider a class of consistent semi-parametric estimators, parameterized with two tuning parameters. Such parameters enables us to have an estimator with a null dominant component of asymptotic bias, and achieve a high efficiency comparatively to other classical estimators. After a brief review of the estimators under study, we provide a Monte Carlo simulation study of the estimators behaviour for some familiar models and for finite sample sizes.

Revisiting the maximum likelihood estimation of a positive extreme value index

Journal of Statistical Theory and Practice, 2014

In this paper we revisit Feuerverger and Hall's maximum likelihood estimation of the extreme value index. Based on those estimators we propose new estimators that have the smallest possible asymptotic variance, equal to the asymptotic variance of the Hill estimator. The full asymptotic distributional properties of the estimators are derived under a general third-order framework for heavy tails. Applications to a real data set and to simulated data are also presented.

Competitive estimation of the extreme value index

Statistics & Probability Letters, 2016

The mean-of-order-p (MO p) extreme value index (EVI) estimators are based on Hölder's mean of an adequate set of statistics, and generalize the classical Hill EVI-estimators, associated with p = 0. Such a class of estimators, dependent on the tuning parameter p ∈ R, has revealed to be highly flexible, but it is not invariant for changes in location. To make the MO p location-invariant, it is thus sensible to use the peaks over a random threshold (PORT) methodology, based upon the excesses over an adequate ascending order statistic. In this article, apart from an asymptotic comparison at optimal levels of the optimal MO p class and some competitive EVI-estimators, like a Pareto probability weighted moments EVI-estimator, a few details on PORT classes of EVI-estimators are provided, enhancing their high efficiency both asymptotically and for finite samples.

Kernel-type estimators for the extreme value index

The Annals of Statistics, 2003

A large part of the theory of extreme value index estimation is developed for positive extreme value indices. The best known estimator for that case is the Hill estimator. This estimator can be considered to be either a moment estimator or a (quasi) maximum likelihood estimator and was generalized to a kernel-type estimator, still only valid for positive extreme value indices. The Hill estimator has been extended to a momenttype estimator valid for all extreme value indices. Also the quasi maximum likelihood estimators based on the generalized Pareto distribution, have been given for a restricted region of negative extreme value indices We derive kernel-type estimators valid for all real extreme value indices and compare their performance with the (generalized) moment estimator and (quasi) maximum likelihood estimator.

Minimum‐variance reduced‐bias estimation of the extreme value index: A theoretical and empirical study

Computational and Mathematical Methods, 2020

In extreme value (EV) analysis, the EV index (EVI), , is the primary parameter of extreme events. In this work, we consider positive, that is, we assume that F is heavy tailed. Classical tail parameters estimators, such as the Hill, the Moments, or the Weissman estimators, are usually asymptotically biased. Consequently, those estimators are quite sensitive to the number of upper order statistics used in the estimation. Minimum-variance reduced-bias (RB) estimators have enabled us to remove the dominant component of asymptotic bias without increasing the asymptotic variance of the new estimators. The purpose of this paper is to study a new minimum-variance RB estimator of the EVI. Under adequate conditions, we prove their nondegenerate asymptotic behavior. Moreover, an asymptotic and empirical comparison with other minimum-variance RB estimators from the literature is also provided. Our results show that the proposed new estimator has the potential to be very useful in practice.