On the Planning and Operations of the Integrated Transit and Mobility-as-a-Service Transportation System: An Equilibrium Analysis Approach

Abstract

Public transportation system not only carries a massive volume of passengers, providing people access to jobs, services, resources, and opportunities but also bears the mission of promoting transportation equity and justice. In the era of rapid informational and vehicular technologies’ development and commercialization, the transportation system is going through a paradigm shift. The shift is symbolized by the birth and growth of the Mobility-as-a-Service (MaaS) system. Its emergence greatly enhances urban mobility by relieving travelers from the strait where traveling is almost equal to owning a personal vehicle or being able to drive. Instead, travel is made into a service that can be provided when needs arise. Under the influence of MaaS, transit services are facing the challenge of ridership decline and the waste of investment. However, opportunities also surface as the idea of public-private partnership is exemplified by the integration of transit and the MaaS system. Although been implemented in practice, the integrated system has not received enough research attention. Existing research oftentimes focuses on either transit or MaaS system and studies the problem within each subsystem independently. The interaction between service providers – transit and MaaS agencies – is largely overlooked, let alone the interaction between service providers and travelers. This dissertation employs an equilibrium analysis approach to derive some knowledge about the planning and operations of the integrated system. Three relatively independent but interconnected studies collectively shed some light on the issue. First, a general demand and supply equilibrium analysis is conducted to gain some basic understandings of the system. Through the modeling of the interactions between the service vehicle drivers and the integrated system riders, key system properties such as decreasing returns to scale and potentials of subsidizing trips are illustrated. Second, a closer look into the demand side equilibrium is cast. By employing a mixed complementarity program describing travelers’ mode and route choice equilibrium behavior, the idea of providing path-based monetary incentivisation is specifically examined. It is found that the mere introduction of the integrated mode can significantly reduce vehicle miles traveled, but the total system travel time can increase or decrease depending on the demand level. Nevertheless, the aspiring finding that the integrated trips take place mostly in areas with limited or no transit services indicates that the integration can be a good complement to the transit system. Third, an operational level study from the mobility service provider’s perspective is carried out. A multi-epoch driverless vehicle fleet rebalancing and dynamic pricing optimization problem is established to capture the leader-follower nature. By anticipating travelers’ mode choice decisions, a mobility service provider sets the price level and relocates idle autonomous vehicles to service riders. With the net revenue maximization operation objective, the improvement of the total revenue generated by the proposed policy is confirmed by comparing with that of a myopic policy. In terms of system performance, it is found that the MaaS operator tends to service regions with good transit coverage while leaving transit-deficient areas under-served. This dissertation gains insights into the integrated system in both the aggregated level for making long-term planning decisions and disaggregated level for developing short-term operational strategies. The acquisition of such insights is critical because both city planners and service providers can draw on and learn from the theoretical research outcome and inform the policy- and decision-making for paving the way for the future transportation system.