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arXiv · 2402.09436

On the expected number of facets for the convex hull of samples

Abstract

This paper studies the convex hull of $d$-dimensional samples i.i.d. generated from spherically symmetric distributions. Specifically, we derive a complete integration formula for the expected facet number of the convex hull. This formula is with respect to the CDF of the radial distribution. As the number of samples approaches infinity, the integration formula enables us to obtain the asymptotic value of the expected facet number for three categories of spherically symmetric distributions. Additionally, the asymptotic result can be applied to estimating the sample complexity in order that the probability measure of the convex hull tends to one.

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Feng Zhao, Xinyi Tong, Shao-Lun Huang. 2024-01-27. On the expected number of facets for the convex hull of samples. https://arxiv.org/abs/2402.09436

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