Simulation based pre-implementation cost evaluation framework for integrated public transit services

The growing demand for integrated and shared mobility services has resulted in a number of public–private partnerships, where public transit agencies and mobility companies collaborate to expand transit service coverage. Nonetheless, many collaborative efforts have failed due to financial restraints and low ridership. The failure of many of the integrated systems can be ascribed to the ineffective pre-implementation evaluation of the integrated system. The lack of a reliable performance evaluation tool capable of assessing the integrated system’s performance prior to implementation could be the case of such failures. Considering this gap, this paper proposes a support tool for decision process of multimodal integrated transport system that examines the viability of an integrated mobility service system comprised of a Fixed Route Transit (FRT) service system and on-demand services. The decision process is powered by an agent-based simulation framework that tests scenarios covering various modal integration strategies. The on-demand services could be Demand Response Transit (DRT) and Transportation Network Company (TNC) services, that particularly act as feeders for FRT to ensure first and last-mile connectivity. This study proposes four integration-strategies with ten potential integration scenarios and four non-integration scenarios, comprising a total of fourteen possible scenarios to complete a trip between any origin–destination pair. Using the agent-based simulation model, various scenarios can be constructed for origin–destination pairs, and based on the generalized system cost, the preferred integration strategy can be selected. The proposed model analyzed the generalized system cost for each scenario by incorporating three key cost components: user cost, agency cost, and external costs. The proposed method was implemented on two different networks, which are the Sioux Falls network and a real-world case study of the Morristown city network in Tennessee, United States. Simulation outcomes indicate that 69% of trips in the Sioux Falls network and 73% of trips in Morristown could be connected to the existing FRT network using feeder services as first and last-mile connectivity solutions. The results suggest that a properly evaluated integrated system could enhance the accessibility of FRT significantly. Therefore, the proposed methodology assesses the advantages of the integrated system prior to its implementation, assisting transit planners and policymakers in the efficient execution of integration strategies and enhancing user experience and mobility.