Private Car Ownership in Presence of Shared Autonomous Vehicles, Case of Tehran

Abstract

With the advent of autonomous vehicles (AVs), researchers have conducted various studies on the impacts of these vehicles, but limited research is found on the influence of AVs on private car ownership. Since AVs are not well-aligned with sustainable development, shared autonomous vehicles (SAVs) would be an appealing alternative. Hence, this paper aims to investigate the impact of socio-economic and travelrelated characteristics on private car ownership in the presence of SAVs among private car users in Tehran. After designing a web-based stated preference (SP) questionnaire and analyzing 2154 valid SP responses in 2022, more than a quarter (26%) of the observations are willing to reduce private car ownership level in presence of SAVs. Estimation results of binary logit model reveal that respondents aged 31-35 and 22-25 years old, as compared to other age categories, are more and less, respectively likely to sell their private cars. Further, due to the fact that users of SAVs, unlike private cars, do not need parking space, respondent are more likely to sell their private cars under this condition. Estimated coefficients of attributes considered in the SP scenarios indicate that increasing each of these attributes (travel time, waiting time, travel cost and number of passengers) in SAVs reduce the likelihood of selling a private car. Another important finding is the impact of respondents' experience with internet taxis (taxis ordered via an app on smartphones); those with frequent use or satisfy with this service, are more likely to reduce their car ownership.