Designing a strategyproof spot market mechanism with many traders: twenty-two steps to Walrasian equilibrium

Abstract

To prove their Walrasian equilibrium existence theorem, Arrow and Debreu (Econometrica 22(3):265–290, 1954) devised an abstract economy that Shapley and Shubik (J Polit Econ 85:937–968, 1977) criticized as a market game because, especially with untrustworthy traders, it fails to determine a credible outcome away from equilibrium. All this earlier work also postulated a Walrasian auctioneer with complete information about traders’ preferences and endowments. To ensure credible outcomes, even in disequilibrium, warehousing is introduced into a multistage market game. To achieve Walrasian outcomes in a large economy with incomplete information, even about traders’ endowments, a strategyproof demand revelation mechanism is considered and then extended to include warehousing.