Policymakers frequently use price regulations as a response to inequality in the markets they control. In this paper, we examine the optimal structure of such policies from the perspective of mechanism design. We study a buyer-seller market in which agents have private information about both their valuations for an indivisible object and their marginal utilities for money. The planner seeks a mechanism that maximizes agents' total utilities, subject to incentive and market-clearing constraints. We uncover the constrained Pareto frontier by identifying the optimal trade-off between allocative efficiency and redistribution. We find that competitive-equilibrium allocation is not always optimal. Instead, when there is inequality across sides of the market, the optimal design uses a tax-like mechanism, introducing a wedge between the buyer and seller prices, and redistributing the resulting surplus to the poorer side of the market via lump-sum payments. When there is significant same-side inequality that can be uncovered by market behavior, it may be optimal to impose price controls even though doing so induces rationing.

中文翻译：

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通过市场重新分配

政策制定者经常使用价格监管来应对他们控制的市场中的不平等。在本文中，我们从机制设计的角度考察了此类政策的最优结构。我们研究了一个买卖双方市场，在这个市场中，代理人拥有关于他们对不可分割对象的估值和他们的货币边际效用的私人信息。规划者寻求一种在激励和市场出清约束下最大化代理人总效用的机制。我们通过确定分配效率和再分配之间的最佳权衡来揭示受约束的帕累托边界。我们发现竞争均衡分配并不总是最优的。相反，当市场两侧存在不平等时，最优设计使用类似税收的机制，在买方和卖方的价格之间引入一个楔子，并通过一次性支付将由此产生的盈余重新分配给市场的较贫穷一方。当市场行为可以发现显着的同侧不平等时，实施价格控制可能是最佳选择，即使这样做会导致配给。