The social dilemma of traffic flow improvement: using the example of Connected Cruise Control

Connected Cruise Control (CCC) is an in-car driver support systems that aims to improve throughput in dense motorway traffic by advising drivers how to drive. The system is currently under development within a HTAS project. It will integrate lane advice, headway advice and speed advice. The advice that drivers receive does not always work in their individual benefit. However, collective action by a greater amount of CCC users can improve the traffic situation as a whole, resulting in reduced overall travel time. Therefore CCC runs the risk of creating a social dilemma (a give-some dilemma). A situation where individual road users contribute to a common good (that is traffic flow) while refraining from actions that would work in their individual benefit, but that on the other hand could pose a harm to traffic flow. We will present the social dilemma underlying traffic flow improvement using the example of CCC. An emphasis is put on (1) benefit perception, (2) individual differences in the evaluation of individual and collective benefits and (3) the perceived inequality of efforts in the creation of a collective benefit. Finally, we will discuss how CCC design can mitigate the dilemma character inherent in traffic flow improvement.