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The Computation of Urban Transportation Congestion Probability and Its Implications for Solving Urban Transportation Problems in China TAN Minghong (Institute of Geographic Science and National Resources Researches, CAS, Beijing 100101, China)
Abstract: Using the mathematics method, this article calculated the urban transportation congestion probability, and analyzed negative externality of traffic congestion caused by the increasing vehicle, and further discussed the implications resulted from this study for solving urban transportation problems in China. The results show that: if urban vehicles and roads synchronously increase, on each road the traffic jam average probability exhibits the trend of the accelerating growth, which can be pictured by the parabola; and along with the size of urban vehicles increase, the traffic jam linearly increases caused by the increase of margin vehicles. In the reality, the rate of urban road increase is lower than that of urban vehicles, and much lower than that of the traffic jam probability. In China, city size is huge, so the traffic congestion externality is obvious. In the municipal areas, the share of transportation land of the whole urban land is very low (around 10%), and the share of urban effective transportation land are smaller. These are important factors affecting urban transportation congestion. In view of the above findings, this article provides some measures for reducing urban transportation jam probability, among which to develop some satellite towns or to establish multi-central land use pattern are essential. Key words: transportation jam; probability; implication; China 本文引用格式： 谈明洪 . 中国城市交通堵塞机率的计算与改善途径 . 地理科学进展， 2010 ，29(1) ：110-116.