The Impact of GPS-Enabled Shortest Path Routing on Mobility: A Game Theoretic Approach

This article investigates the impact of app use on traffic patterns. With ubiquity of traffic information and the increased use of routing apps, urban and suburban areas in the US have seen a recent rise in “cut-through” traffic and related congestion patterns. This increase is suspected to be both an instantaneous phenomenon (a natural response of routing apps to special events, accidents, or other problems reducing capacity locally in transportation networks) and a trend (progressive increase of such traffic over time, with a corresponding shift in demand on the transportation network). Data is presented that supports both theories on the I-210 corridor in the LA Basin. Then, two models (including a new one) are presented to capture these phenomena. The models are extensions of known user equilibrium formulations that take into account routing preferences of motorists when using apps. The ability of the models to capture the trends observed in field data (and often mentioned in the popular media) are validated on benchmark examples for the same corridor. Simulations are run in which the percentage of routing app users is progressively increased to demonstrate the impact of these apps on traffic patterns and, in particular, potential convergence to Nash equilibria solutions of traffic flow problems. Finally, large-scale simulations using the micro-simulation tool Aimsun are also shown to recreate these issues.