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An Naturalistic Experiment to Simulate AV Impacts on Travel Patterns


Giovanni Circella (UC Davis) and Joan Walker (UC Berkeley)

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Mustapha Harb, Jai Malik


This study was made possible through funding received by the University of California Institute of Transportation Studies from the State of California through the Public Transportation Account and the Road Repair and Accountability Act of 2017 (Senate Bill 1), the Alfred P. Sloan Foundation, and the 3 Revolutions Future Mobility Program of the University of California Davis. We would like to thank Patricia Mokhtarian, Maximilian Auffhammer, Michael Anderson Mollie D’Agostino for their contribution to study. We also thank all participants in a meeting of the advisory board for this project that helped shape the research. Finally, we thank Bruce Griesenbeck and Shengyi Gao from SACOG for providing the 2018 SACOG household travel diary dataset used in this study. We also thank the colleagues from SACOG for helping us recruit participants in the study and providing feedback at all stages of the research


To explore potential travel behavior shifts induced by personally owned, fully autonomous vehicles (AVs), we ran an experiment that provided personal chauffeurs to households to simulate life with an AV. Like an advanced AV, chauffeurs take over driving duties. The pilot study was conducted in 2017 with 13 households living in the San Francisco Bay Area recruited through a convenience sampling approach. In the second wave, conducted in the period August 2019 to March 2020, households were recruited from the 2018 Sacramento household travel survey sample. Sampling was stratified by weekly vehicle miles traveled (VMT), and households were selected to be diverse by demographics, modal preferences, mobility barriers, and residential location. In the second wave, thirty-four households received 60 hours of chauffeur service for one week, and nine households received 60 hours per week for two weeks. Smartphone-based travel diaries were recorded for the chauffeur week(s), one week before, and one week after.



  • Harb, M., Xiao, Y., Circella, G., Mokhtarian, P. L., & Walker, J. L. (2018). Projecting travelers into a world of self-driving vehicles: estimating travel behavior implications via a naturalistic experiment. Transportation45(6), 1671-1685.





  • Harb, M., Malik, J.,Circella, G., & Walker, J. (2021)“A Glimpse of the Future: Simulating Life with Personally-Owned Autonomous Vehicles and Their Implications on Travel-Related Behaviors”, accepted for presentation at the 100th Annual Meeting of the Transportation Research Board, online conference, January 2021, Paper #21-04145.