ABSTRACT
Road Star Rating (SR) is a system used by iRAP (International Road Assessment Program) to quantify the level of road safety. It is based on an estimated score (SRS) which is computed by considering road attributes affecting the road safety and subsequently used to design investment plans for safer roads. However, the outputs of iRAP are four independent SRs, each are for an individual road user group: vehicle occupant, motorcyclist, pedestrian, and bicyclist. Therefore, this paper aims to develop an aggregated star rating to quantify the overall level of roads’ risk. The reason behind this topic is simplifying the design of the investment plan which depends on the iRAP’s SR and increasing the applicability of the iRAP models for strategic decision making. Four statistical aggregation functions are suggested to aggregate the four SRSs and each of them is then evaluated with the view to select the most proper function.
