Application of grey relational analysis for evaluating road traffic safety measures: advanced driver assistance systems against infrastructure redesign

Two of the main approaches to improve traffic safety are extensive redesign of the physical road infrastructure and large-scale implementation of advanced driver assistance systems. These approaches are to a large extent substitutes, but also partly complementary. Evaluation of alternative strategic investments in either of the two, and combinations, is complicated by limitations in availability, reliability and accuracy of data. Some of the evaluation methods most commonly used in transportation research are reviewed, and a method that is rather unknown in the western world and that is especially capable of dealing with part of these limitations is introduced. Grey relational analysis (GRA) - a normalisation-based method - provides a simple and transparent evaluation procedure from which a clear-cut ranking order of strategies derives. The application of GRA to the stated evaluation problem is illustrated with a case study in The Netherlands