Strategy-Proofness and Single-Crossing
分析了个体在有限有序社会备选方案上具有单交叉偏好时的防策略性集体选择规则，证明了匿名、一致且防策略的社会选择规则等价于扩展中位数规则，并为中位数投票者定理提供了策略基础。
This paper analyzes strategy-proof collective choice rules when individuals have single-crossing preferences on a finite and ordered set of social alternatives. It shows that a social choice rule is anonymous, unanimous, and strategy-proof on a maximal single-crossing domain if and only if it is an extended median rule with n-1 fixed ballots distributed over the individuals' most preferred alternatives. As a by-product, the paper also proves that strategy-proofness implies the tops-only property. It also offers a strategic foundation for the so-called "single-crossing version" of the Median Voter Theorem, by showing that the median ideal point can be implemented in dominant strategies by a direct mechanism in which every individual reveals his true preferences.