A Unique Informationally Efficient and Decentralized Mechanism with Fair Outcomes
证明，在经典纯交换经济中，任何实现公平分配的信息去中心化机制，其消息空间维度至少为代理人数量乘以商品数量；而均等收入瓦尔拉斯机制恰好达到这一维度，因此是信息有效的，并且是唯一实现公平分配的信息有效机制。
It is shown that any informationally decentralized mechanism that realizes fair allocations over the class of classical pure exchange environments has a message space of dimension no smaller than the number of agents times the number of commodities. Since the equal income Walrasian mechanism, in which all agents take prices parametrically and maximize utility subject to the average income constraint, realizes fair outcomes over the class of classical pure exchange environments and has a message space of that dimension it is informationally efficient. Further, it is shown that it is the unique informationally efficient mechanism realizing fair allocations.