Understand Users' Privacy Perception and Decision of V2X Communication in Connected Autonomous Vehicles

Connected autonomous vehicles (CAVs) offer opportunities to improve road safety and enhance traffic efficiency. Vehicleto-everything (V2X) communication allows CAVs to communicate with any entity that may affect, or may be affected by, the vehicles. The implementation of V2X in CAVs is inseparable from sharing and receiving a wide variety of data. Nevertheless, the public is not necessarily aware of such ubiquitous data exchange or does not understand their implications. We conducted an online study (N = 595) examining drivers' privacy perceptions and decisions of four V2X application scenarios. Participants perceived more benefits but fewer risks of data sharing in the V2X scenarios where data collection is critical for driving than otherwise. They also showed more willingness to share data in those scenarios. In addition, we found that participants' awareness of privacy risks (priming) and their experience on driving assistance and connectivity functions impacted their data-sharing decisions. Qualitative data confirmed that benefits, especially safety, come first, indicating a privacy-safety tradeoff. Moreover, factors such as misconceptions and novel expectations about CAV data collection and use moderated participants' privacy decisions. We discuss implications of the obtained results to inform CAV privacy design and development. In this work, we fill the gap toward understanding users' privacy perception and decision of V2X communication in CAVs. We examine whether, how and why users' privacy perceptions and decisions vary among different V2X application categories. To inform the design of privacy risk communication in CAVs, we also investigate whether priming would change users' privacy perceptions and decisions. Moreover, we explore whether users' prior experience in connectivity and driving assistance functions would have any influences. We conducted an online experiment (N = 595) on Amazon Mechanical Turk (MTurk) using a mixed design. There were three between-subjects conditions: control, privacy priming, privacy&security priming. Participants were informed of potential privacy risks of data disclosure in the privacy-priming condition. Security risks of receiving data were further shown in the privacy&security-priming condition. The four V2X communication applications were within-subjects: 1) cooperative autonomous driving, 2) road safety, 3) traffic management, and 4) infotainment, comfort and convenience [30] . During the study, participants viewed one scenario describing the data exchange and its purpose of each application. For each scenario, participants indicated their 1) perceived benefits, 2) perceived risks, 3) data-sharing decision, and 4) data-sharing decision confidence. We also asked an open-ended question at the end to understand why participants chose to share or not share their data in each scenario. We obtained several important findings. First, participants perceived more benefits but fewer risks in the three scenarios where data sharing is critical to driving than otherwise. Their privacy decisions were aligned with such privacy perceptions (Sections 4.1 & 4.2). Response to the open-end questions confirmed that participants believed that safety comes first, indicating the critical role of privacy-safety tradeoff (Section 4.5). Second, the privacy priming was effective in encouraging safer data-sharing decisions in general. Yet, the extra security priming did not increase the priming effect (Sections 4.1 & 4.2). Moreover, participants' prior experience in connectivity and driving assistance functions impacted perceived benefits and risks of data sharing, as well as privacy decisions (Section 4.3). In summary, the contributions of our work include: • We conduct an online study investigating users' privacy perception and decision of V2X communication for CAVs as a result of considering benefits and privacy risks of sharing data, and benefits and security risks of receiving data. • Besides privacy-utility tradeoff, our results suggest the critical role of privacy-safety tradeoff in users' datasharing decisions of V2X communication in CAVs. • We identify various factors (e.g., safety, privacy priming, and prior experience) that can influence people's perceived benefits, privacy risks, and data-sharing decisions of V2X communication in CAVs.