Discrete Mathematics ( IF 0.7 ) Pub Date : 2021-02-02 , DOI: 10.1016/j.disc.2020.112282 Nathan Albin , Jason Clemens , Derek Hoare , Pietro Poggi-Corradini , Brandon Sit , Sarah Tymochko
Random spanning trees of a graph are governed by a corresponding probability mass distribution (or “law”), , defined on the set of all spanning trees of . This paper addresses the problem of choosing in order to utilize the edges as “fairly” as possible. This turns out to be equivalent to minimizing, with respect to , the expected overlap of two independent random spanning trees sampled with law . In the process, we introduce the notion of homogeneous graphs. These are graphs for which it is possible to choose a random spanning tree so that all edges have equal usage probability. The main result is a deflation process that identifies a hierarchical structure of arbitrary graphs in terms of homogeneous subgraphs, which we call homogeneous cores. A key tool in the analysis is the spanning tree modulus, for which there exists an algorithm based on minimum spanning tree algorithms, such as Kruskal’s or Prim’s.
中文翻译:
随机生成树的最佳边缘使用率和最小预期重叠
图的随机生成树 由相应的概率质量分布(或“定律”)控制, ,定义在的所有生成树的集合上 。本文解决选择的问题为了尽可能“公平地”利用边缘。事实证明,相对于,两个依法采样的独立随机生成树的预期重叠 。在此过程中,我们介绍了齐次图的概念。这些图可以选择一个随机生成树,以便所有边具有相等的使用概率。主要结果是一个放气过程,该过程根据齐次子图(我们称为齐次核心)识别任意图的层次结构。分析中的关键工具是生成树模量,为此,存在一种基于最小生成树算法的算法,例如Kruskal或Prim。