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arXiv · 2203.16233

Robust signal dimension estimation via SURE

Joni Virta·Niko Lietzen·Henri Nyberg
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Abstract

The estimation of signal dimension under heavy-tailed latent factor models is studied. As a primary contribution, robust extensions of an earlier estimator based on Gaussian Stein's unbiased risk estimation are proposed. These novel extensions are based on the framework of elliptical distributions and robust scatter matrices. Extensive simulation studies are conducted in order to compare the novel methods with several well-known competitors in both estimation accuracy and computational speed. The novel methods are applied to a financial asset return data set.

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Joni Virta, Niko Lietzen, Henri Nyberg. 2022-03-30. Robust signal dimension estimation via SURE. https://arxiv.org/abs/2203.16233

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