Equilibrium Inverse Reinforcement Learning for Ride-hailing Vehicle Network
This addresses the challenge of optimizing ride-hailing services under driver uncertainty, offering a scalable solution for real-world applications.
The paper tackles the problem of passenger-vehicle matching in ride-hailing networks by formulating it as a multi-agent equilibrium policy and learning driver reward functions transferable to different dynamics, achieving significant improvements in imitation accuracy over baselines with computational times of only a few seconds on a single CPU.
Ubiquitous mobile computing have enabled ride-hailing services to collect vast amounts of behavioral data of riders and drivers and optimize supply and demand matching in real time. While these mobility service providers have some degree of control over the market by assigning vehicles to requests, they need to deal with the uncertainty arising from self-interested driver behavior since workers are usually free to drive when they are not assigned tasks. In this work, we formulate the problem of passenger-vehicle matching in a sparsely connected graph and proposed an algorithm to derive an equilibrium policy in a multi-agent environment. Our framework combines value iteration methods to estimate the optimal policy given expected state visitation and policy propagation to compute multi-agent state visitation frequencies. Furthermore, we developed a method to learn the driver's reward function transferable to an environment with significantly different dynamics from training data. We evaluated the robustness to changes in spatio-temporal supply-demand distributions and deterioration in data quality using a real-world taxi trajectory dataset; our approach significantly outperforms several baselines in terms of imitation accuracy. The computational time required to obtain an equilibrium policy shared by all vehicles does not depend on the number of agents, and even on the scale of real-world services, it takes only a few seconds on a single CPU.