Inference with an Incomplete Model of English Auctions
基于两个简单假设构建英式拍卖的不完全模型，在对称独立私人价值范式下，推导出竞拍者需求分布、最优保留价和协变量效应的信息边界，并通过蒙特卡洛实验和实证应用展示其性能。
While English auctions are the most common in practice, their rules typically lack sufficient structure to yield a tractable theoretical model without significant abstractions. Rather than relying on one stylized model to provide an exact interpretation of the data, we explore an incomplete model based on two simple assumptions: bidders neither bid more than their valuations nor let an opponent win at a price they would be willing to beat. Focusing on the symmetric independent private values paradigm, we show that this limited structure enables construction of informative bounds on the distribution function char-acterizing bidder demand, on the optimal reserve price, and on the effects of observable covariates on bidder valuations. If the standard theoretical model happens to be the true model, our bounds collapse to the true features of interest. In contrast, when the true data-gen-erating process deviates in seemingly small ways from that implied by equilibrium in the standard theoretical model, existing methods can yield misleading results that need not even lie within our bounds. We report results from Monte Carlo experiments illustrating the perform-ance of our approach and comparing it to others. We apply our ap-