## 7 Review of Studies Related to Integration in the Context of Multi-Modal Mobility
### Review of Studies
Question: How to extend the concept of Mobility as a Service (MaaS) to fully integrate public transportation to make public transport an attractive alternative to private transport? Results: By extending smart ticketing systems in airline industry with governance and operational processes, fully incorporating operators and utilizing their self-interest to deliver commercially viable and attractive integrated public transport services to consumers, the concept of Collaboration as a Service was proposed in the paper [111] to fully integrate public transportation. 8. Question: How to systematically support alliance formation in MaaS? Results: MaaS relies on integration of various forms of public and private transport services based on collaboration of transport service providers. Forming an alliance is an effective approach to facilitate collaboration of transport service providers. In the study [106], a conceptual model was proposed and ten fundamental propositions for alliance formation were formulated to offer MaaS systems. The proposed alliance formation model was applied in a MaaS pilot in the Netherlands. The proposed alliance formation model and the propositions provide the necessary prerequisites for the design of a governance structure to provide MaaS services. Question: How can a public transport authority develop MaaS in rural areas through integrating a public transport service with carpooling? Results: MaaS involves the integration of different travel modes into an integrated transport service to handle bookings and payments for individual trips. The study [112] presents how a public transport authority developed a MaaS in rural areas through integrating a public transport service with carpooling throughout the development of a project 10. Question: How to simulate autonomous mobility-on-demand systems to evaluate its impact from the perspectives of travelers, operators and the city? Results: In [82], simulation of autonomous mobility-on-demand systems was achieved through co-simulation of two agent-based simulators, MATSim and IMSim, with the former generating transport demand and allocating travelers according to their preferences whereas the latter providing operational execution of transport fleets. The simulation method was applied to probe into the challenges to offer ridesharing services with autonomous vehicles. 11. Question: What are the characteristics of a MaaS service and how to compare different services, understand the potential effects of MaaS, and integrate the societal goals into MaaS services? Results: In the study [113], a topology of MaaS was proposed as a tool to characterize and discuss MaaS. The proposed topology consists of MaaS Levels 0 to 4 to characterize different degrees of integration, where Level 0 denotes no integration; Level 1 denotes integration of information; Level 2 denotes integration of booking and payment; Level 3 denotes integration of the service offer, including contracts and responsibilities; Level 4 denotes integration of societal goals. The levels were used to describe their added value, technical requirements and implications for society, business and users/customers. 12. Question: How to assess the effects of ridesourcing services on service providers and the transport system by simulation? Results: The study [83] presented how to integrate sharing and non-sharing based ridesourcing services into mobiTopp, an agent-based travel demand model by including a vehicle allocation and fleet control component and extending the mode choice by the ridesourcing service to assess the effects of ridesourcing services on service providers and the transport system. In the study, the results concerning performance indices for providers (e.g., the number of bookings, trip times, and occupation rates and influence on other travel modes) for up to 1600 vehicles were analyzed. The analysis is helpful to gain insights into interdependencies between ridesourcing services and other travel modes and paves the way for the planning and regulation of ridesourcing services. 13.