Destabilization effect of international trade in a perfect foresight dynamic general equilibrium model

In the present paper, we consider a two-country, two-good, two-factor general equilibrium model with CIES nonlinear preferences, asymmetric technologies across countries and decreasing returns to scale. It is shown that aggregate instability and endogenous fluctuations may occur due to international trade. In particular, we prove that the integration into a common market on which countries trade the produced good and the capital input may lead to period-two cycles even when the closed-economy equilibrium is saddle-point stable in both countries.     

Time consistency and optimal government policies in perfect foresight equilibrium

This paper develops a framework for determining optimal monetary and fiscal policies in perfect foresight equilibrium. Such equilibria have the property that all underlying demand and supply functions are derived from optimizing behavior, expectations are realized, and all markets clear. The time consistency of optimal policies derived under such circumstances is analyzed for a variety of alternative optimal policy problems. The general conclusion is that time consistency will prevail with respect to the optimization of any single policy instrument which does not appear explicitly in the indirect utility functions; otherwise time inconsistency will result. Monetary instruments are generally examples of the former, and fiscal instruments examples of the latter.     

Effect of restricting asset trade in dynamic equilibrium models

Abstract. This paper shows that differences between the predictions of an international real business cycle model with complete markets and the predictions of a model where agents can trade only risk-free bonds depend heavily on three parameters: discount factor, and degrees of persistence and spillovers in productivity shocks. This sensitivity explains apparently paradoxical results previously obtained in the literature. Also, since empirical work finds that two of those parameters are not estimated precisely, the outcomes of quantitative studies comparing complete-markets and bond economies using only the point estimates of those parameters inherit the substantial uncertainty in the parameter estimates.     

Predator-prey and neo-classical models of cyclical growth

Journal of Economics -     

Equilibrium, stability, and deficit financing in a simple nonlinear monetary model under perfect foresight

This paper shows how the nonlinearities associated with inflation taxes and interest payments give rise to problems of nonexistence and nonuniqueness of equilibria. For any choice of fiscal and monetary policy parameters, two sets of steady state equilibria are identified. One of these is associated with a nonzero rate of inflation and depends upon both the monetary and fiscal policy parameters. The other is associated with a stable price level and is independent of the monetary policy parameter. The stability properties resulting from the interaction between the sign and size of the budget deficit and alternative modes of deficit financing are analyzed. These depend critically upon the associated steady state and a variety of types of behavior may result.     

Global stability of dynamic models

A necessary and sufficient condition for global stability of dynamic models is summability to one of the long-run elasticities and cointegration. The short-run coefficients automatically satisfy the homogeneity condition. A relevant restriction has to be imposed in the parameter estimation process; otherwise, the ratios of variables appearing in the model will tend to either infinity or zero, which is economic nonsense in most cases. This conclusion is particularly important for the ECM or VEC (SVEC) models that decompose behavior into long and short-run parts.     

Risk-dominance and perfect foresight dynamics in N-player games

In perfect foresight dynamics, an action is linearly stable if expectation that people will always choose the action is self-fulfilling. A symmetric game is a PIM game if an opponent's particular action maximizes the incentive of an action, independently of the rest of the players. This class includes supermodular games, games with linear incentives and so forth. We show that, in PIM games, linear stability is equivalent to u-dominance, a generalization of risk-dominance, and that there is no path escaping a u-dominant equilibrium. Existing results on N-player coordination games, games with linear incentives and two-player games are obtained as corollaries.     

Market structure and competitive equilibrium in dynamic economic models

Recently theorists have analyzed economies which potentially contain both finite and infinite horizon overlapping generations, using “Arrow-Debreu” (complete) markets. Typically, applied models assume recursive spot and contingent securities markets, implying a different equilibrium concept. Indeed, if infinite horizon agents are present recursive equilibria cannot exist without some side conditions on debt. With the right side conditions, we show that every recursive market equilibrium allocation is a complete market equilibrium allocation and vice versa. This bridges a gap between theory and applications, and extends existing equivalence results on market structure.     

Inflation aversion and macroeconomic policy in a perfect foresight monetary model

This paper reexamines monetary non-superneutrality and the optimality of the optimum quantity of money in the money-in-utility Sidrauski model with endogenous fluctuations of the time preference by introducing inflation aversion. It is shown that the long-run superneutrality of the standard Sidrauski model does not hold, and Friedman's optimum quantity of money is not optimal.     

Existence and local indeterminacy of periodic equilibrium paths in infinite horizon models with external effects

Summary. It is expected that every periodic equilibrium path may exist even under standard assumptions such as low discounting and the concavity of utility functions in infinite horizon models with external effects. Nevertheless, until now no such example has been presented. In this note we will first construct a bounded growth model that has an external effect and every periodic equilibrium path under any discount factor. Next we will study the conditions under which periodic equilibrium paths have a local indeterminacy. Received: December 23, 1998; revised version: April 19, 1999     

On the existence of pure-strategy perfect equilibrium in discontinuous games

We provide sufficient conditions for a (possibly) discontinuous normal-form game to possess a pure-strategy trembling-hand perfect equilibrium. We first show that compactness, continuity, and quasiconcavity of a game are too weak to warrant the existence of a pure-strategy perfect equilibrium. We then identify two classes of games for which the existence of a pure-strategy perfect equilibrium can be established: (1) the class of compact, metric, concave games satisfying upper semicontinuity of the sum of payoffs and a strengthening of payoff security; and (2) the class of compact, metric games satisfying upper semicontinuity of the sum of payoffs, strengthenings of payoff security and quasiconcavity, and a notion of local concavity and boundedness of payoff differences on certain subdomains of a player's payoff function. Various economic games illustrate our results.     

The stability threshold and two facets of polarization

In this paper we introduce the stability threshold that quantifies the minimal returns to size sufficient to prevent credible secession threats by regions of the country. Severity of internal tension has been linked to degree of polarization of citizens’ preferences and characteristics. We show that the increasing degree of polarization does not, in general, raise the stability threshold, even though this hypothesis holds in some asymptotic sense. We also examine the question of the number of smaller countries to be created if the unity of the large country is not sustainable, and investigate the link between this number and the degree of the country polarization. JEL Classification Numbers H20, D70, D73     

Quotas and equilibrium relative prices in the trade restricting country

This paper is concerned with the effects of international trade restriction through quotas. It is shown that a casual relationship exists between the fraction of licences distributed domestically, the terms of trade, and the domestic relative price of the importable.     

Gradualism and dynamic trade adjustment: Revisiting the pro-trade effect of free trade agreements

Do pro-trade effects of free trade agreements reflect timing of policy or dynamic trade adjustment? Only the latter involves dynamic welfare gains. I find that dynamic trade adjustment is as important as the immediate impact effect of free trade agreements.     

Relaxing the sure-solvency conditions in temporary equilibrium models

The usual temporary equilibrium results hold when sure-solvency conditions are appropriately relaxed. Preferences over potentially bankrupt states are represented by an extension of the indirect utility function for negative wealth. For models without institutional constraints such as margin requirements, sure-solvency can be replaced by unbounded aversion to bankruptcy. For models with institutional constraints, sure-solvency can be replaced by a weaker limit on maximum loss (or expected loss).     

Proper belief revision and equilibrium in dynamic games

We present a theory of rationality in dynamic games in which players, during the course of the game, may revise their beliefs about the opponents’ utility functions. The theory is based upon the following three principles: (1) the players’ initial beliefs about the opponents’ utilities should agree on some profile u of utility functions, (2) every player should believe, at each of his information sets, that his opponents are carrying out optimal strategies and (3) a player at information set h should not change his belief about an opponent's ranking of strategies a and b if both a and b could have led to h. Scenarios with these properties are called preference conjecture equilibria for the profile u of utility functions. We show that every normal form proper equilibrium for u induces a preference conjecture equilibrium for u, thus implying existence of preference conjecture equilibrium.     

On the stability of the stackelberg oligopoly equilibrium

The stability of the equilibrium in the Stackelberg undifferentiated oligopoly model where each oligopolist strives for leadership is analyzed for general demand and cost functions and for a discrete system with non-instantaneous adjustment.     

APEC实现自由贸易安排的路径思考及我国的策略选择

在特定的历史背景条件下形成和发展起来的亚太经济合作组织(APEC),其运行机制的灵活性、渐进性、开放性以及自主自愿等特点适应了APEC各成员经济体的多样性差异,推动了亚太地区经济合作的发展.     

Stochastic evolutionary stability in extensive form games of perfect information

Nöldeke and Samuelson [Games Econ. Behav. 5 (1993) 425] investigate a stochastic evolutionary model for extensive form games and show that even for games of perfect information with a unique subgame perfect equilibrium, non-subgame perfect equilibrium-strategies may well survive in the long run even when mutation rates tend to zero. In a different model of evolution in the agent normal form of these games Hart [Games Econ. Behav. 41 (2002) 227] shows that under suitable limit-taking, where small mutation rates are accompanied by large population sizes in a particular way, the unique prediction is again the subgame perfect equilibrium. This paper provides a proof of a similar result for the model of Nöldeke and Samuelson.     

Multiple equilibria in bargaining models of decentralized trade

Summary A market in which population size is endogenously determined is modeled. Buyers and sellers are randomly matched upon entering the market, whereupon they engage in non-cooperative bilateral bargaining. It is shown that general matching technologies and heterogeneity of buyer or seller populations often result in multiple market equilibria. Up to four equilibria can occur and the equilibria can always be ranked according to population size. Under some conditions all equilibria can also be Pareto ranked. The set of equilibria depends on the relative population sizes of different types of potential entrant, market entry costs, and the degree of differentiation between agents on the same side of the market.This paper evolved from a chapter in my dissertation. I am indebted to Leo Simon for many helpful conversations. Michael Hanemann, Jeff Perloff, Stefan Reichelstein, Jim Vercammen, Brian Wright, and participants in seminars at U.C. Berkeley, the University of Maryland, the University of British Columbia and the Australian National University also provided useful comments. Lastly, I benefited greatly from the thorough comments and corrections provided by an anonymous referee.