Abstract
We introduce a non-parametric robust and asymptotically unbiased estimator for the tail index of a conditional Pareto-type response distribution in presence of random covariates. The estimator is obtained from local fits of the extended Pareto distribution to the relative excesses over a high threshold using an adjusted minimum density power divergence estimation technique. We derive the asymptotic properties of the proposed estimator under some mild regularity conditions, and also investigate its finite sample performance with a small simulation experiment. The practical applicability of the methodology is illustrated on a dataset of calcium content measurements of soil samples.
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The authors are very grateful to the two anonymous referees for their very constructive comments on the paper. The suggestions have definitely improved the presentation of the material.
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Dierckx, G., Goegebeur, Y. & Guillou, A. Local robust and asymptotically unbiased estimation of conditional Pareto-type tails. TEST 23, 330–355 (2014). https://doi.org/10.1007/s11749-013-0350-6
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DOI: https://doi.org/10.1007/s11749-013-0350-6