A new measure for evaluating level of service for traffic operational systems

This paper proposes a new measure to evaluate level of service for traffic operation based on the process capability indices (PCIs). A brief introduction to the concepts of PCIs and the characteristics of traffic flow is presented and followed by a discussion on the appropriateness of applying PCIs to measure the quality of traffic flow. Several case studies have conducted to investigate the effectiveness of the proposed new measure for traffic LOS and the results indicate that the speed and density are the most appropriate parameters for this purpose. The paper concludes with directions for future works.