Understanding individuals’ choice-making mechanism in trip chains of shared autonomous vehicles

Abstract

Since shared autonomous vehicles (SAVs) are expected to become an essential transportation mode, lots of research has been conducted to investigate people’s attitudes toward SAV and their behaviors in specific situations. Most studies have focused on the single trip service of SAVs, but in fact users always travel in trip chains with multiple sub-trips. To address this research gap, this study provides insights into a trip-chain based service in SAV systems. When users need a short-time stay in a trip chain, they can choose paying and keeping the same SAV (PKSS) to continue their trips, or recalling a new SAV (RNS) after the stay. To reveal users’ decision-making mechanisms, a stated preference (SP) survey is designed and implemented in Beijing, China. Then a hybrid choice model (HCM) framework is adopted to analyze critical factors under various trip scenarios. The results show that stay time, price (CNY/min) for PKSS, and waiting time for RNS are three crucial factors determining users’ choice-making. Users’ choice-making in the current sub-trip is related to other sub-trips features in a trip chain. Further, people who are more concerned about convenience and time-sensitivity are more likely to choose PKSS. Finally, the impacts of operators’ level of services are deeply analyzed to understand users’ decision-making. This paper can be beneficial for SAV operators to provide trip-chain based service in term of service pattern, key findings (suggestions), and the foundation for SAVs’ optimization operation.