RT Journal Article SR 00 ID 10.1214/21-AOS2087 A1 Usseglio-Carleve, Antoine A1 Girard, Stéphane A1 Stupfler, Gilles Claude T1 Extreme conditional expectile estimation in heavy-tailed heteroscedastic regression models JF The Annals of statistics YR 2021 FD 2021-12 VO vol. 49 IS n° 6 SP 3358 OP 3382 K1 Expectiles, Extreme value analysis, Heavy-tailed distribution, Heteroscedasticity, Regression models, Residual-based estimators, Single-indes model, Tail empirical process of residuals AB Expectiles define a least squares analogue of quantiles. They have been the focus of a substantial quantity of research in the context of actuarial and financial risk assessment over the last decade. The behaviour and estimation of unconditional extreme expectiles using independent and identically distributed heavy-tailed observations has been investigated in a recent series of papers. We build here a general theory for the estimation of extreme conditional expectiles in heteroscedastic regression models with heavy-tailed noise; our approach is supported by general results of independent interest on,residual-based extreme value estimators in heavy-tailed regression models, and is intended to cope with covariates having a large but fixed dimension. We demonstrate how our results can be applied to a wide class of important examples, among which linear models, single-index models as well as ARMA and GARCH time series models. Our estimators are showcased on a numerical simulation study and on real sets of actuarial and financial data. PB Institute of Mathematical Statistics SN 2168-8966 LK https://publications.ut-capitole.fr/id/eprint/43653/ UL http://tse-fr.eu/pub/125766