Online Decentralised Mechanisms for Dynamic Ridesharing

Nicos Protopapas, Vahid Yazdanpanah, Enrico H. Gerding, Sebastian Stein

Abstract: Ridesharing services promise an exciting new future for urban mobility. A carefully designed ridesharing system will decrease congestion levels and increase air quality. However, an effective system needs to capture online demand, where users do not schedule their trips in advance, but instead appear and ask for a ride right away. Such online demands require rerouting to be efficient. We call this setting with online demands and available rerouting "dynamic ridesharing'' and propose a market-based mechanism where the prospective riders are provided with a menu of choices between several available cars. Our algorithm incentivises users to share their rides and guarantees riders' utility by properly compensating riders whose routes change during their journey. We provide numerical results, comparing our algorithm against natural benchmarks representing real-world ridesharing services for several cases and with respect to efficiency, fairness, and environmental impact.