Knowledge that Transforms

A common finding in many of the recent empirical studies with the ARCH class of models applied to high frequency financial data concerns the apparent persistence of shocks for forecast of the future conditional variances. It is likely that several different variables share this same implied long-run component, however. In that situation, the variables are defined to be copersistent in variance. Conditions for copersistence to occur in the linear multivariate GARCH model are presented. These conditions parallel the conditions for linear cointegration in the mean. A simple empirical example with foreign exchange rate data illustrates the ideas. Copyright 1993 by The Econometric Society.

Internal consistency of choice has been a central concept in economics, decision theory, and social choice. This idea is essentially confused. We cannot determine whether a choice function is consistent without referring to something external to choice (e.g., objectives, values). The standard results have to be reexamined in this light. Kenneth J. Arrow's general possibility theorem is extended in this paper without demanding any internal consistency of social choice or any notion of 'social rationality.' Copyright 1993 by The Econometric Society.

A two-person game is of conflicting interests if the strategy to which player one would most like to commit herself holds player two down to his minimax payoff. Suppose there is a positive prior probability that player one is a "commitme nt type" who will always play this strategy. Then player one will get a t least her commitment payoff in any Nash equilibrium of the repeated game if her discount factor approaches one. This result is robust against further perturbations of the informational structure and in striking contrast to the message of the Folk theorem for games with incomplete information. Copyright 1993 by The Econometric Society.

This paper studies the role and implications of price advertising when shopping trips are costly to consumers. The authors present a model where consumers search sequentially and where stores advertise the price. Their model has a unique equilibrium exhibiting price dispersion. The model generates predictions about the shape of the price distribution and firms' advertising behavior. Also when the initial advertising costs are precisely zero, entry drives the equilibrium to the perfectly competitive outcome; while otherwise entry drives prices higher. Finally, when advertising costs shrink, prices become competitive; however, when search costs shrink, prices remain bounded above marginal production costs. Copyright 1993 by The Econometric Society.

The author shows how a group of individuals can learn to play a coordination game without any common knowledge and with only a small amount of rationality. The game is repeated many times by different players. Each player chooses an optimal reply based on incomplete information about what other players have done in the past. Occasionally they make mistakes. When the likelihood of mistakes is very small, typically one coordination equilibrium will be played almost all of the time over the long run. This stochastically stable equilibrium can be computed analytically using a general theorem the author proves on perturbed Markov processes.

This paper provides a simulated moments estimator (SME) of the parameters of dynamic models in which the state vector follows a time-homogeneous Markov process. Conditions are provided for both weak and strong consistency as well as asymptotic normality. Various tradeoff's among the regularity conditions underlying the large sample properties of the SME are discussed in the context of an asset pricing model.

A global game is an incomplete information game where the actual payoffstructure is determined by a rairdom draw from a given class of games and where each player makes a noisy observation of the selected game.For 2 x 2 games, it is shown that equilibrium play in a global game with vanishing noise forces the players to conform to Harsanyi and Selten's risk dominance criterion.When the uncertainty is one-dimensional, the result may be obtained by repeated elimination of dominated strategies in the global game."1'his pxper is a combinat.ion,and a subatantial generalization, of Carlxson (19R9) and Carlason and Van Damme (1989).Some basic ideas on global games and their telation to risk dominance originate from a note, written by Cadseon in 1985.The suthora thank R.einhard Selten, Lars-Gunnar Svensson, Jdrgen Weibull and various seminar audiences Cor helpful comments.The conatructive criticiam of several referees considerably improved the paper's quality.

Three theorems state conditions sufficient for the inessentiality of equilibrium in a pure exchange, sequence economy. The agents have uncommon priors, state-contingent utility functions, and asymmetric information in every trading period, and they trade different sets of event-contingent claims in different periods. The theorems provide alternative interpretations of the concept of market completeness, reveal two fundamentally different ways to obtain inessentiality, and shed light on the conditions permitting speculation and the role of price-contingent trading. None of the theorems requires ex ante Pareto optimality or the absence of arbitrage opportunities. Copyright 1993 by The Econometric Society.

ABSTRACT Since 1973 technological, political, regulatory, and economic forces have been changing the worldwide economy in a fashion comparable to the changes experienced during the nineteenth century Industrial Revolution. As in the nineteenth century, we are experiencing declining costs, increasing average (but decreasing marginal) productivity of labor, reduced growth rates of labor income, excess capacity, and the requirement for downsizing and exit. The last two decades indicate corporate internal control systems have failed to deal effectively with these changes, especially slow growth and the requirement for exit. The next several decades pose a major challenge for Western firms and political systems as these forces continue to work their way through the worldwide economy.