While multimodal mobility systems have the potential to bring many benefits to travelers, drivers, the environment, and traffic congestion, such systems typically involve multiple non-cooperative decision-makers who may selfishly optimize their own objectives without considering the overall system benefits. This paper aims to investigate market-based interactions of travelers and ride-sourcing drivers in the context of multimodal mobility systems. We propose a unified mathematical modeling framework to capture the decentralized travelers and drivers' decision-making process and balance the network's demand and supply by equilibrium pricing. Such a model allows analyses of the impact of decentralized decision-making on multimodal mobility efficiencies. The proposed formulation can be further convexified to efficiently compute the equilibrium ride-sourcing prices. We conduct numerical experiments on different settings of transportation networks to gain policy insights. We find that travelers prefer ride-sourcing and multimodal transportation more than the driving option when they are more sensitive to prices. We also find that travelers may need to be subsidized to use multimodal transportation when there is fewer transit hubs in the network or, ride-sourcing drivers become too sensitive to the prices. However, we find that more transit hubs in the network increases the total empty VMT of ride-sourcing drivers by increasing the total relocation time. The proposed model can be used by policymakers and platform operators to design pricing and subsidy schemes that align individual decision-making with system-level efficiency and evaluate the trade-offs between accessibility and environmental impacts in multimodal transportation networks.

翻译：尽管多模态出行系统有潜力为出行者、驾驶员、环境及交通拥堵带来诸多益处，但此类系统通常涉及多个非合作决策者，他们可能自私地优化自身目标而忽略整体系统效益。本文旨在研究多模态出行系统背景下出行者与网约车驾驶员基于市场的交互行为。我们提出了一个统一的数学建模框架，以刻画去中心化的出行者与驾驶员的决策过程，并通过均衡定价平衡网络供需。该模型可用于分析去中心化决策对多模态出行效率的影响。所提模型可进一步凸化以高效计算均衡网约车价格。我们在不同交通网络设置下进行了数值实验以获取政策启示。研究发现，当出行者对价格更敏感时，相较于自驾选项，他们更倾向于选择网约车及多模式出行。研究还发现，当网络中交通枢纽较少或网约车驾驶员对价格过于敏感时，可能需要补贴出行者以促使其使用多模式出行。然而，研究发现网络中更多的交通枢纽会因增加总体调遣时间而导致网约车驾驶员空驶总里程增加。所提模型可供政策制定者与平台运营商用于设计使个体决策与系统效率相协调的定价与补贴方案，并评估多模式交通网络中可达性与环境影响之间的权衡关系。