Strategy-proofness in the Large

• 成果类型: Article
• 署名作者: Azevedo, Eduardo M.; Budish, Eric
• 署名单位: University of Pennsylvania; University of Chicago
• 刊物名称: REVIEW OF ECONOMIC STUDIES
• ISSN/ISSBN: 0034-6527
• DOI: 10.1093/restud/rdy042
• 发表日期: 2019
• 页码: 81-116
• 关键词: approximate competitive-equilibrium; incentive compatibility; school choice; natural experiment; EFFICIENCY; implementation; mechanisms; STABILITY; MARKET; allocation

摘要

We propose a criterion of approximate incentive compatibility, strategy-proofness in the large (SP-L), and argue that it is a useful second-best to exact strategy-proofness (SP) for market design. Conceptually, SP-L requires that an agent who regards a mechanisms prices as exogenous to her reportube they traditional prices as in an auction mechanism, or price-like statistics in an assignment or matching mechanismuhas a dominant strategy to report truthfully. Mathematically, SP-L weakens SP in two ways: (1) truth-telling is required to be approximately optimal (within epsilon in a large enough market) rather than exactly optimal, and (2) incentive compatibility is evaluated ex interim, with respect to all full-support i.i.d. probability distributions of play, rather than ex post with respect to all possible realizations of play. This places SP-L in between the traditional notion of approximate SP, which evaluates incentives to manipulate ex post and as a result is too strong to obtain our main results in support of SP-L, and the traditional notion of approximate Bayes-Nash incentive compatibility, which, like SP-L, evaluates incentives to manipulate ex interim, but which imposes common knowledge and strategic sophistication assumptions that are often viewed as unrealistic.