English

Pairwise optimal coupling of multiple random variables

Probability 2021-05-10 v2 Combinatorics

Abstract

We generalize the optimal coupling theorem to multiple random variables: Given a collection of random variables, it is possible to couple all of them so that any two differ with probability comparable to the total-variation distance between them. In a number of cases we show that the disagreement probability we achieve is the best possible. The proofs of sharpness rely on new results in extremal combinatorics, which may be of independent interest.

Keywords

Cite

@article{arxiv.1903.00632,
  title  = {Pairwise optimal coupling of multiple random variables},
  author = {Omer Angel and Yinon Spinka},
  journal= {arXiv preprint arXiv:1903.00632},
  year   = {2021}
}

Comments

18 pages, 4 figures. Revised introduction. Improved and simplified some results and proofs

R2 v1 2026-06-23T07:56:07.166Z