In a new paper which has been published today in the European Journal of Transport and Infrastructure Research (EJTIR), we study how people weigh fatalities caused by self-driving cars differently from fatalities caused by human drivers, and we show how part of this difference relates to a reference-level effect that is often seen in moral choice contexts. Lead author of the paper is Bing Huang; Caspar Chorus and Sander van Cranenburgh are co-authors. Here is the abstract:
Although Automated vehicles (AVs) are expected to have a major and positive effect on road safety, recent accidents caused by AVs tend to generate a powerful negative impact on the public opinion regarding safety aspects of AVs. Triggered by such incidents, many experts and policy makers now believe that paradoxically, safety perceptions may well prohibit or delay the rollout of AVs in society, in the sense that AVs will need to become much safer than conventional vehicles (CVs), before being accepted by the public. In this study, we provide empirical insights to investigate and explain this safety paradox. Using stated choice experiments, we show that there is indeed a difference between the weight that individuals implicitly attach to an AV-fatality and to a CV-fatality. However, the degree of overweighting of AV-fatalities, compared to CV-fatalities, is considerably smaller than what has been suggested in public opinions and policy reports. We also find that the difference in weighting between AV-fatalities and CV-fatalities is (partly) related to a reference level effect: simply because the current number of fatalities caused by AVs is extremely low, each additional fatality carries extra weight. Our findings suggest that indeed, AVs have to become safer—but not orders of magnitude safer—than CVs, before the general public will develop a positive perception of AVs in terms of road safety. Ironically, our findings also suggest that the inevitable occurrence of more AV-related road accidents will in time lead to a diminishing degree of overweighting of safety issues surrounding the AV.
