Tai Wei Hu

On the Coexistence of Money and Higher-Return Assets and its Social Role

This paper adopts mechanism design to tackle the central issue in monetary theory, namely, the coexistence of money and higher-return assets. I describe an economy with pairwise meetings, where fiat money and risk-free capital compete as means of payment. Whenever fiat money has an essential role, any constrained-efficient allocation is such that capital commands a higher rate of return than fiat money.

On p-rationalizability and approximate common certainty of rationality

Abstract This paper shows that common p-belief of rationality implies p-rationalizability for games with compact strategy sets. We also establish the Bayesian foundation for the perfect p-rationalizability for finite games. The p-rationalizability is then used to analyze the robustness of rationalizable sets. For any game with compact strategy sets, we show that the rationalizable set is robust, i.e., the strategies characterized by common p-belief of rationality are close to the rationalizable set when p → 1 .

Information aggregation in a large multi-stage market game

A three-stage market-game mechanism is devised that is simple (actions are quantities and outcomes are determined by arithmetic operations that do not depend on details of the economy) and achieves efficiency in a two-divisible-good, pure-exchange setting with potential information-aggregation. After an entry stage, agents make offers which are provisional for all but a small, randomly selected group. Then, those offers are announced, and everyone else makes new offers with payoffs determined by a Shapley–Shubik market game. For a finite and large number of players, there exists an almost ex post efficient equilibrium. Conditions for uniqueness are also provided.

Decentralizing constrained-efficient allocations in the Lagos–Wright pure currency economy

This paper offers two ways to decentralize the constrained-efficient allocation of the Lagos–Wright (2005) pure currency economy. The first way has divisible money, take-it-or-leave-it offers by buyers, and a transfer scheme financed by money creation. If agents are sufficiently patient, the first best is achieved for finite money growth rates. If agents are impatient, the equilibrium allocation approaches the constrained-efficient allocation asymptotically as the money growth rate tends to infinity. The second way has indivisible money, take-it-or-leave-it offers by buyers, and no government intervention. We discuss the strict implementation of constrained-efficient allocations and the applicability of our scheme to economies with Lucas trees, endogenous participation, match-specific heterogeneity, and sequential competitive markets.