Abstract: A system of tradable travel credits is proposed for managing traffic congestion in general networks. A social planner is assumed to initially distribute a certain number of travel credits to all eligible travellers, and then there are link-specific charges to travelers using that link. Free trading of credits among travelers is assumed. For a given credit distribution and credit charging scheme, the existence of a unique equilibrium link flow pattern is demonstrated with either fixed or elastic demand. It can be obtained by solving a standard traffic equilibrium model subject to a total credit consumption constraint. The credit price at equilibrium in the trading market is also conditionally unique. The appropriate distribution of credits among travelers and correct selection of link-specific rates is shown to lead to the most desirable network flow patterns in a revenue-neutral and equitable manner. Social optimum, Pareto-improving and revenue-neutral, and side-constrained traffic flow patterns are investigated. The tradable credit scheme thus offers a powerful tool to manage network mobility, traffic congestion and environmental quality in an effective, efficient and equitable manner.

Bio
Prof. Hai Yang is currently a Professor in the Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology. He received his Bachelor degree from Wuhan University, China, and PhD from Kyoto University, Japan. Prof. Yang specializes in analysis, modeling and optimization of transportation systems and transportation economics. He is internationally known as one of the most active scholars in the field of transportation, with more than 160 papers published in SCI/SSCI indexed journals and an H-index citation rate of 31. Most of his publications appeared in leading international journals, such as Transportation Research, Transportation Science and Operations Research. Prof. Yang served as editor/guest editors or editorial advisory board members for a number of international journals. Currently, he serves as associate/area editors of two major international journals in the transportation field: Transportation Research Part B and ASCE Journal of Transportation Engineering. In recognition of his outstanding research, Prof. Yang has received a number of national and international awards including JSCE Outstanding Paper Award (1991), Distinguished Overseas Young Investigator Award from the National Natural Science Foundation of China (NSFC) (2004), National Natural Science Award bestowed by the State Council of the People's Republic of China (2011), HKUST School of Engineering Research Excellence Awards (2012). Recently, Prof Yang was appointed as the third Editor-in-Chief of Transportation Research Part B, a leading journal in the field of transportation, since its inception in 1967.