English

On weak $\epsilon$-nets and the Radon number

Combinatorics 2019-03-01 v3 Computational Geometry Discrete Mathematics

Abstract

We show that the Radon number characterizes the existence of weak nets in separable convexity spaces (an abstraction of the euclidean notion of convexity). The construction of weak nets when the Radon number is finite is based on Helly's property and on metric properties of VC classes. The lower bound on the size of weak nets when the Radon number is large relies on the chromatic number of the Kneser graph. As an application, we prove a boosting-type result for weak ϵ\epsilon-nets.

Keywords

Cite

@article{arxiv.1707.05381,
  title  = {On weak $\epsilon$-nets and the Radon number},
  author = {Shay Moran and Amir Yehudayoff},
  journal= {arXiv preprint arXiv:1707.05381},
  year   = {2019}
}

Comments

Accepted to SoCG '19, modified according to comments by reviewers

R2 v1 2026-06-22T20:49:38.371Z