Dominance-based rough set approach: An application case study for setting speed limits for vehicles in speed controlled zones

Speed management represents an important strategy in order to improve road safety, because a strong relationship is between speed and crash occurrence and severity. Speed limits enforcement is the main measure to control operating speeds but to obtain the compliance of drivers, the limits must be safe but also credible. This means that road users have to regard the speed limit as logical under given conditions and so a speed limit is credible if it fits the image evoked by the road. This paper describes the development of a Decision Support System (DSS) for the selection of safe and credible speed limits for speed zones. The proposed DSS is based on Dominancebased Rough Set Approach (DRSA), which presents interesting advantages in terms of transparency and manageability with respect to many other decision support competitive methodologies. In fact DRSA, after getting the preferred information necessary to set up the decision model, in terms of exemplary decisions, allows to build a multi-criteria model expressed in terms of ”if..., then ...” decision rules. The proposed multi-criteria decision approach aims to suggest to decision-makers a safe and credible speed limit for speed zones, taking into consideration many factors such as accident rate, roadway geometry, roadway development, traffic and others.