Improvement Project Choice Based on Efficiency Analysis

Traditionally, the evaluation of the road improvement project is mainly based on the indexes of V/C ratio and travel speed, aiming at improving the traffic performance (Chen, 2002). However, the improvement can guarantee neither the decrease of the spatiotemporal cost of single vehicle, nor the increase of the transportation efficiency. The evaluation is typically a problem of multi-input and multi-output, on which the traditional method fails to create the connection among all the inputs and the traffic performance, and the results selection is apt to be affected by subjective factors. Based on efficiency analysis theory, using data envelopment analysis, this paper builds a CCR model to evaluate an alternative scheme and to analyze and diagnose the ineffective scheme. This paper adopts the popular HCM analysis method and analyzes fluctuation of the index with time and exterior operation conditions (National Research Council, 2000). Results show that travel delay is more appropriate as the traffic operation index in the complex roadway environment. Moreover, approximate calculation methods of this index are discussed.