This article studies cost-plus-time (A+B) procurement contracting with time incentives in the highway construction industry. In the presence of construction uncertainty, the contractor's actual completion time may deviate from the bid completion time, and the A+B contract design is not ex post efficient. Using data from highway procurement contracts in California, we show that an ex post efficient lane rental contract would reduce the social cost by $41.39 million (43.11%) on average. Moreover, the average commuter cost would decrease by $62.06 million (78.96%), suggesting a substantial reduction in the construction externality to commuters from lane rental contracts.

中文翻译：

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采购合同的不确定性与时间激励

本文研究了高速公路建设行业中具有时间激励的成本加时间 (A+B) 采购合同。在存在施工不确定性的情况下，承包商的实际完工时间可能会偏离投标完成时间，A+B合同设计事后效率不高。使用加利福尼亚州高速公路采购合同的数据，我们表明事后高效的车道租赁合同将平均减少 4139 万美元（43.11%）的社会成本。此外，平均通勤成本将减少 6206 万美元（78.96%），表明车道租赁合同对通勤者的建设外部性大幅减少。