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arXiv · 1902.01136

Directional differentiability for supremum-type functionals: statistical applications

Javier Cárcamo·Luis-Alberto Rodríguez·Antonio Cuevas
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Abstract

We show that various functionals related to the supremum of a real function defined on an arbitrary set or a measure space are Hadamard directionally differentiable. We specifically consider the supremum norm, the supremum, the infimum, and the amplitude of a function. The (usually non-linear) derivatives of these maps adopt simple expressions under suitable assumptions on the underlying space. As an application, we improve and extend to the multidimensional case the results in \cite{Raghavachari} regarding the limiting distributions of Kolmogorov-Smirnov type statistics under the alternative hypothesis. Similar results are obtained for analogous statistics associated with copulas. We additionally solve an open problem about the Berk-Jones statistic proposed by \cite{Jager-Wellner-2004}. Finally, the asymptotic distribution of maximum mean discrepancies over Donsker classes of functions is derived.

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Javier Cárcamo, Luis-Alberto Rodríguez, Antonio Cuevas. 2019-02-04. Directional differentiability for supremum-type functionals: statistical applications. https://arxiv.org/abs/1902.01136

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