Rationalizable Trade

We formulate necessary and sufficient conditions for interim rationalizable trade between two players.

Are the anti-globalists right? Gains-from-trade without a Walrasian auctioneer

We examine whether the "fear" of globalisation can be rationalised by economic theory. To do so, we depart from the standard AD/AS (partial) equilibrium model where the coordinational role of the Auctioneer is substituted by an implementation device based on learning (Guesnerie, 1992). By endowing producers with a learning ability to forecast market prices, individual profit-maximizing production decisions become interdependent in a strategic sense (strategic substitutes). Performing basic comparative statics exercises, we show that "competitiveness" matters in a precise sense: as foreign producers gain access to the home market, home producers' ability to forecast market prices is undermined, so being their ability to forecast the profit consequences of their production decisions. When performing a standard open economy exercise in such a framework, we show that the existence of standard efficiency gains - due to the increase in competition (or spatial price stabilization) - is traded-off against coordination upon the welfare enhancing free-trade equilibrium (stabilizing price expectations). Therefore, we identify a new rationale for an exogenous price intervention in open economy targeting coordination, to allow trading countries to fully reap the benefits from trade. We illustrate this point showing that classical measures evaluating ex-ante the desirability of economic integration (net welfare gains) do not always advice integration between two expectationally stable economies

Pareto-Optimal Matching Allocation Mechanisms for Boundedly Rational Agents

This article is concerned with the welfare properties of trade when the behavior of agents cannot be rationalized by preferences. I investigate this question in an environment of matching allocation problems. There are two reasons for doing so: rstly, the niteness of such problems entails that the domain of the agents' choice behavior does not need to be restricted in any which way to obtain results on the welfare properties of trade. Secondly, some matching allocation mechanisms have been designed for non-market environments in which we would typically expect boundedly rational behavior. I nd qualied support for the statements that all outcomes of trade are Pareto-optimal and all Pareto optima are reachable through trade. Contrary to the standard case, dierent trading mechanisms lead to dierent outcome sets when the agents' behavior is not rationalizable. These results remain valid when restricting attention to \minimally irrational" behavior.Bounded Rationality, House Allocation Problems, Fundamental Theorems of Welfare, Multiple Rationales

Proper Consistency

Proper consistency is defined by the properties that each player takes all opponent strategies into account (is cautious) and deems one opponent strategy to be infinitely more likely than another if the opponent prefers the one to the other (respects preferences). When there is common certain belief of proper consistency, a most preferred strategy is properly rationalizable. Any strategy used with positive probability in a proper equilibrium is properly rationalizable. Only strategies that lead to the backward induction outcome is properly rationalizable in the strategic form of a generic perfect information game. Proper rationalizability can be used to test the robustness of inductive procedures.

Are the antiglobalists right? Gains-from-trade without a walrasian auctioneer

We examine whether the "fear" of globalisation can be rationalised by economic theory. To do so, we depart from the standard AD/AS (partial) equilibrium model where the coordinational role of the Auctioneer is substituted by an implementation device based on learning (Guesnerie, 1992). By endowing producers with a learning ability to forecast market prices, individual profit-maximizing production decisions become interdependent in a strategic sense (strategic substitutes). Performing basic comparative statics exercises, we show that "competitiveness" matters in a precise sense: as foreign producers gain access to the home market, home producers' ability to forecast market prices is undermined, so being their ability to forecast the profit consequences of their production decisions. When performing a standard open economy exercise in such a framework, we show that the existence of standard efficiency gains - due to the increase in competition (or spatial price stabilization) - is traded-off against coordination upon the welfare enhancing free-trade equilibrium (stabilizing price expectations). Therefore, we identify a new rationale for an exogenous price intervention in open economy targeting coordination, to allow trading countries to fully reap the benefits from trade. We illustrate this point showing that classical measures evaluating ex-ante the desirability of economic integration (net welfare gains) do not always advice integration between two expectationally stable economies.open economy ; rational expectations ; coordination ; common knowledge

Auctions with Variable Supply: Uniform Price versus Discriminatory

We examine an auction in which the seller determines the supply after observing the bids. We compare the uniform price and the discriminatory auction in a setting of supply uncertainty. Uncertainty is caused by the interplay of two factors: the seller's private information about marginal cost, and the seller's incentive to sell the profit-maximizing quantity given the received bids. In every symmetric mixed strategy equilibrium, bidders submit higher bids in the uniform price auction than in the discriminatory auction. In the two-bidder case this result extends to the set of rationalizable strategies. As a consequence, we find that the uniform price auction generates higher expected revenue for the seller and higher trade volume.sealed bid multi-unit auctions, variable supply auctions, discriminatory and uniform price auctions, subgame perfect equilibria, rationalizable strategies

Are the anti-globalists right? Gains-from-trade without a Walrasian auctioneer

We examine whether the "fear" of globalisation can be rationalised by economic theory. To do so, we depart from the standard AD/AS (partial) equilibrium model where the coordinational role of the Auctioneer is substituted by an implementation device based on learning (Guesnerie, 1992). By endowing producers with a learning ability to forecast market prices, individual profit-maximizing production decisions become interdependent in a strategic sense (strategic substitutes). Performing basic comparative statics exercises, we show that "competitiveness" matters in a precise sense: as foreign producers gain access to the home market, home producers' ability to forecast market prices is undermined, so being their ability to forecast the profit consequences of their production decisions. When performing a standard open economy exercise in such a framework, we show that the existence of standard efficiency gains - due to the increase in competition (or spatial price stabilization) - is traded-off against coordination upon the welfare enhancing free-trade equilibrium (stabilizing price expectations). Therefore, we identify a new rationale for an exogenous price intervention in open economy targeting coordination, to allow trading countries to fully reap the benefits from trade. We illustrate this point showing that classical measures evaluating ex-ante the desirability of economic integration (net welfare gains) do not always advice integration between two expectationally stable economies. <br><br> Keywords; globalisation, rational expectations, coordination, common knowledge

Common Knowledge of Rationality and Market Clearing in Economies with Asymmetric Information

Consider an exchange economy with asymmetric information. What is the set of outcomes that are consistent with common knowledge of rationality and market clearing? To address this question we define an epistemic model for the economy that provides a complete description not only of the beliefs of each agent on the relationship between states of nature and prices but also of the whole system of interactive beliefs. The main result, theorem 1, provides a characterization of outcomes that are consistent with common knowledge of rationality and market clearing (henceforth, CKRMC outcomes) in terms of a solution notion - Ex - Post Rationalizability - that is defined directly in terms of the parameters that define the economy. We then apply theorem 1 to characterize the set of CKRMC outcomes in a general class of economies with two commodities. CKRMC manifests several intuitive properties that stand in contrast to the full revelation property of Rational Expectations Equilibrium: In particular, we obtain that for a robust class of economies: (1) there is a continuum of prices that are consistent with CKRMC in every state of nature, and hence these prices do not reveal the true state, (2) the range of CKRMC outcomes is monotonically decreasing as agents become more informed about the economic fundamentals, and (3) trade is consistent with common knowledge of rationality and market clearing even when there is common knowledge that there are no mutual gains from trade.common knowledge, rationality, rationalizability, rationalizable expectations

Rationalizable Trade

We formulate necessary and sufficient conditions for interim rationalizable trade between two players