A Dynamic Tree Algorithm for Peer-to-Peer Ride-sharing Matching

TL;DR

This paper introduces a dynamic tree algorithm for peer-to-peer ride-sharing matching that improves runtime efficiency and scalability by leveraging driver schedules and candidate request pre-processing.

Contribution

The paper presents a novel dynamic tree algorithm tailored for on-demand ride-sharing, enhancing matching efficiency and incorporating a pre-processing step for candidate selection.

Findings

The algorithm achieves similar objective function values as exact methods with shorter runtimes.

Performance is affected by spatial distribution of participants.

Excess travel times are critical constraints impacting matching quality.

Abstract

On-demand peer-to-peer ride-sharing services provide flexible mobility options, and are expected to alleviate congestion by sharing empty car seats. An efficient matching algorithm is essential to the success of a ride-sharing system. The matching problem is related to the well-known dial-a-ride problem, which also tries to find the optimal pickup and delivery sequence for a given set of passengers. In this paper, we propose an efficient dynamic tree algorithm to solve the on-demand peer-to-peer ride-sharing matching problem. The dynamic tree algorithm benefits from given ride-sharing driver schedules, and provides satisfactory runtime performances. In addition, an efficient pre-processing procedure to select candidate passenger requests is proposed, which further improves the algorithm performance. Numerical experiments conducted in a small network show that the dynamic tree algorithm reaches the same objective function values of the exact algorithm, but with shorter runtimes. Furthermore, the proposed method is applied to a larger size problem. Results show that the spatial distribution of ride-sharing participants influences the algorithm performance. Sensitivity analysis confirms that the most critical ride-sharing matching constraints are the excess travel times. The network analysis suggests that small vehicle capacities do not guarantee overall vehicle-kilometer travel savings.