An Algorithmic Approach to Line Construction in Existing Transit Networks

TL;DR

This paper introduces an algorithm for designing new transit lines within existing networks without altering current infrastructure, and analyzes how different parameters affect the efficiency of the resulting network.

Contribution

It presents a novel algorithm for line construction in existing transit networks and a method to evaluate network efficiency, considering various parameters and objectives.

Findings

New lines generally improve network efficiency

Algorithm performance depends on chosen pathfinding and evaluation methods

Cost factors can lead to less efficient network designs

Abstract

Transit networks often have existing infrastructure that cannot be modified when designing new lines for the network. This paper provides an algorithm to generate a line within a transit network without changing any existing lines or connections between stations. Additionally, a method of analyzing the efficiency of a transit line and network is provided, and used within the algorithm presented. An analysis of the effects of different parameters and objectives on the location of a new line is performed. We find that under most cases, a new line generated improves the overall efficiency of the network, while under certain circumstances, an unsuitable combination of pathfinding algorithm and efficiency evaluation method or an increase in construction and maintenance cost can cause the algorithm to create a less efficient network.