Abstract: On the theory of optimizing the social surplus, congestion pricing equals to the social marginal cost of the corresponding link over urban road network. The strategy of congestion pricing might trade off the effect of external diseconomy caused by network congestion, and the price of congestion is tantamount to the difference between social and private marginal costs. The implementation of congestion pricing brings to the maximization of social surplus, but leads the loss of users’surplus and causes the problems in social equity.

Key words: social surplus, congestion pricing, social marginal cost

摘要： 在社会剩余最大化情况下，城市道路网络中各个路段的拥挤费用等于相应的社会边际费用，道路拥挤收费可以抵消交通拥挤产生的外部不经济性，拥挤费用等于社会边际费用与用户边际费用的差额。通过拥挤收费使得社会剩余达到最大，同时导致用户剩余的损失，并衍生社会公平性问题。

关键词: 社会剩余, 道路拥挤收费, 社会边际费用