English

The k-interchange-constrained diameter of a transit network: A connectedness indicator that accounts for travel convenience

Data Structures and Algorithms 2020-08-28 v1 Discrete Mathematics

Abstract

We study two variants of the shortest path problem. Given an integer k, the k-color-constrained and the k-interchange-constrained shortest path problems, respectively seek a shortest path that uses no more than k colors and one that makes no more than k - 1 alternations of colors. We show that the former problem is NP-hard, when the latter is tractable. The study of these problems is motivated by some limitations in the use of diameter-based metrics to evaluate the topological structure of transit networks. We notably show that indicators such as the diameter or directness of a transit network fail to adequately account for travel convenience in measuring the connectivity of a network and propose a new network indicator, based on solving the k-interchange-constrained shortest path problem, that aims at alleviating these limitations.

Keywords

Cite

@article{arxiv.2008.12259,
  title  = {The k-interchange-constrained diameter of a transit network: A connectedness indicator that accounts for travel convenience},
  author = {Nassim Dehouche},
  journal= {arXiv preprint arXiv:2008.12259},
  year   = {2020}
}