中文摘要：

特许期结构是政府进行BOT特许协议决策的重要内容.以BOT道路为研究对象,通过考虑实际完工时间以及需求的不确定性,比较了单阶段和两阶段特许期结构对私人部门收益、社会福利以及消费者剩余的影响.研究结果表明单阶段特许期结构可以带来更高的私人部门收益和社会福利,而两阶段特许期结构在道路需求价格弹性较小时可以产生更高的消费者剩余.

英文摘要：

Concession structures play an important role in the government＇s decisions on BOT concessions. This paper compares the profit of the private sector, social welfare, and consumer surplus under single-period and two period concession structures by taking into account both demand uncertainty and the uncertainty of actual construction completion dates for BOT road projects. The results show that both the private sector＇s profit and social welfare are higher under the single-period concession structure. However, when the price elasticity of traffic demand is sufficiently low, the consumer surplus is higher under the two-period concession structure.