English

Order distances and split systems

Discrete Mathematics 2019-10-23 v1 Combinatorics

Abstract

Given a distance DD on a finite set XX with nn elements, it is interesting to understand how the ranking Rx=z1,z2,,znR_x = z_1,z_2,\dots,z_n obtained by ordering the elements in XX according to increasing distance D(x,zi)D(x,z_i) from xx, varies with different choices of xXx \in X. The order distance Op,q(D)O_{p,q}(D) is a distance on XX associated to DD which quantifies these variations, where qp2>0q \geq \frac{p}{2} > 0 are parameters that control how ties in the rankings are handled. The order distance Op,q(D)O_{p,q}(D) of a distance DD has been intensively studied in case DD is a treelike distance (that is, DD arises as the shortest path distances in an edge-weighted tree with leaves labeled by XX), but relatively little is known about properties of Op,q(D)O_{p,q}(D) for general DD. In this paper we study the order distance for various types of distances that naturally generalize treelike distances in that they can be generated by split systems, i.e. they are examples of so-called l1l_1-distances. In particular we show how and to what extent properties of the split systems associated to the distances DD that we study can be used to infer properties of Op,q(D)O_{p,q}(D).

Keywords

Cite

@article{arxiv.1910.10119,
  title  = {Order distances and split systems},
  author = {Vincent Moulton and Andreas Spillner},
  journal= {arXiv preprint arXiv:1910.10119},
  year   = {2019}
}
R2 v1 2026-06-23T11:51:38.815Z