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arXiv · 2103.16084

Public Transport Planning: When Transit Network Connectivity Meets Commuting Demand

Sheng Wang·Yuan Sun·Christopher Musco·Zhifeng Bao
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Abstract

In this paper, we make a first attempt to incorporate both commuting demand and transit network connectivity in bus route planning (CT-Bus), and formulate it as a constrained optimization problem: planning a new bus route with k edges over an existing transit network without building new bus stops to maximize a linear aggregation of commuting demand and connectivity of the transit network. We prove the NP-hardness of CT-Bus and propose an expansion-based greedy algorithm that iteratively scans potential candidate paths in the network. To boost the efficiency of computing the connectivity of new networks with candidate paths, we convert it to a matrix trace estimation problem and employ a Lanczos method to estimate the natural connectivity of the transit network with a guaranteed error bound. Furthermore, we derive upper bounds on the objective values and use them to greedily select candidates for expansion. Our experiments conducted on real-world transit networks in New York City and Chicago verify the efficiency, effectiveness, and scalability of our algorithms.

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Sheng Wang, Yuan Sun, Christopher Musco, Zhifeng Bao. 2021-03-30. Public Transport Planning: When Transit Network Connectivity Meets Commuting Demand. https://doi.org/10.1145/3448016.3457247

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