Using Bid Rotation and Incumbency to Detect Collusion: A Regression Discontinuity Approach
研究如何通过分析中标与未中标报价非常接近的拍卖，区分由成本差异导致的分配模式与由非竞争环境导致的模式，并将方法应用于美国俄亥俄州牛奶拍卖和日本市政采购拍卖数据。
Abstract Cartels participating in procurement auctions frequently use bid rotation or prioritize incumbents to allocate contracts. However, establishing a link between observed allocation patterns and firm conduct has been difficult: there are cost-based competitive explanations for such patterns. We show that by focusing on auctions in which the winning and losing bids are very close, it is possible to distinguish allocation patterns reflecting cost differences across firms from patterns reflecting non-competitive environments. We apply our tests to two datasets: the sample of Ohio milk auctions studied in Porter and Zona (1999, “Ohio School Milk Markets: An Analysis of Bidding”, RAND Journal of Economics, 30, 263–288), and a sample of municipal procurement auctions from Japan.