Robust and smooth estimation of the extreme tail index via weighted minimum density power divergence
摘要
We propose a robust and smooth estimator for the tail index of Pareto-type distributions, based on a weighted density power divergence. By incorporating a weight function, our approach enhances efficiency in the presence of outliers, providing a robust extension of both weighted least squares and kernel-based tail index estimators. We establish consistency and asymptotic normality of the proposed estimators, and conduct a simulation study to evaluate their finite-sample performance relative to existing methods. Finally, the practical relevance and improved reliability of our approach are illustrated through an application to Danish fire insurance data.