Halo Effects of Automated Speed Enforcement: A Literature Review

摘要

With the increasing evidences of halo effects regarding automated speed enforcement (ASE), an empirical review is conducted to analyze the findings of previous literatures. 24 studies are filtered to evaluated the three types of halo effects. The current paper find that the typical existence of distance halo is associated with fixed cameras, while spillover effect and time halo are in related to mobile cameras. There are limited literatures to investigate relative contributors, although factors such as ASE type, visibility, warnings, roads, and vehicles are proved to be related to characteristics of various halo effects. Moreover, this review reveals the essence of halo effects, which represented three dimensions of enforcement impact (two spatial dimensions and one temporal dimension). This paper also provides a potential repeated enforcement assumption to explain the time halo. Limitations of the existing studies have been discussed.