Ride-sharing, combining multiple trips, can significantly contribute to sustainable urban mobility. It's most efficient in high-demand areas with similar trip requests. However, this study reveals that people's willingness to share rides doesn't always follow this trend. A model of individual ride-sharing incentives reveals two adoption regimes: one with constant adoption, and another with decreasing adoption as demand increases. A discontinuous transition between these regimes occurs at high demand, switching abruptly from low to high ride-sharing adoption. Analysis of over 360 million ride requests in New York City and Chicago shows both regimes coexist, consistent with model predictions. Even moderate increases in financial incentives could significantly impact individual user group ride-sharing adoption.

David-Maximilian Storch, Marc Timme, Malte Schröder