Caratheodory's Theorem in Depth
نویسندگان
چکیده
Let X be a finite set of points in R. The Tukey depth of a point q with respect to X is the minimum number τX(q) of points of X in a halfspace containing q. In this paper we prove a depth version of Carathéodory’s theorem. In particular, we prove that there exists a constant c (that depends only on d and τX(q)) and pairwise disjoint sets X1, . . . , Xd+1 ⊂ X such that the following holds. Each Xi has at least c|X| points, and for every choice of points xi in Xi, q is a convex combination of x1, . . . , xd+1. We also prove depth versions of Helly’s and Kirchberger’s theorems.
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ورودعنوان ژورنال:
- Discrete & Computational Geometry
دوره 58 شماره
صفحات -
تاریخ انتشار 2017