Centralized and decentralized algorithms for two-to-one matching problem in ridehailing systems

In the context of on-demand ridehailing, we propose a heuristic matching algorithm where a passenger can share their ride with one more passenger while experiencing a high-quality service with a minimal increase in travel time. To evaluate the performance, we implemented the algorithm in a traffic microsimulator and compared it with a ride-matching algorithm developed by Simonetto et al. (2019) at IBM. Moreover, to enhance efficiency and reduce computational time, we proposed a decentralized version that is based on vehicle-to-infrastructure (V2I) and infrastructure-to-infrastructure (I2I) communication. Application on the downtown Toronto road network demonstrated that the service rate in the centralized version improved by 24%, compared to the IBM algorithm. The decentralized version demonstrated a 25.53 times speedup and the service rate improved by 19%, compared to the IBM algorithm. Furthermore, a sensitivity analysis was conducted over both centralized and decentralized versions to address how different variables and parameters can affect the system's performance.