Knowledge that Transforms

A new definition of strategic stability is shown to satisfy all of the requirements given by Elon Kohlberg and Jean-Francois Mertens (1986). The definition follows the general form of the original definition of Kohlberg and Mertens, but, rather than working with perturbations of the payoffs or strategy space, works directly with perturbations to the best reply correspondence. With the appropriate topology on this space of perturbations, the resulting definition does satisfy all of the requirements given by Kohlberg and Mertens. It is shown that one does not have much freedom in the topology one uses. Copyright 1990 by The Econometric Society.

The paper develops a model of retirement based on the option value of continuing to work.Continuing to work maintains the option of retiring on more advantageous terms later.The model is used to estimate the effects on retirement of firm pension plan provisions.Typical defined benefit pension plans in the United States provide very substantial incentives to remain with the firm until some age, often the early retirement age, and then a strong incentive to leave the firm thereafter.(This may be a major reason for the rapidly declining labor force participation rates of older workers in the United States.)The model fits firm retirement data very well; it captures very closely the sharp discontinuous jumps in retirement rates at specific ages.The model is used to simulate the effect on retirement of potential changes in pension plan provisions.Increasing the age of early retirement from 55 to 60, for example, would reduce firm departure rates between ages 50 and 59 by almost forty percent.

The author builds a theory of the choice of techniques in joint production, at a given profit rate, considering a market algorithm. Partial results are extended by means of an abstract notion of technology, where techniques meet demand and satisfy local properties. Global results on the existence, uniqueness, and convergence towards an equilibrium technique are obtained. The author, thus, characterizes cases where a square technique is reached, which provides an answer to an old debate, initiated by W. S. Jevons, between classical and neoclassical economists. But the framework allows for a more general interpretation in terms of two-level planning procedures. Copyright 1990 by The Econometric Society.

Individuals with finite private information independently choose acts and messages. Their utilities may depend on all acts and information, including the center's. Incentive payments are separable and fully transferable. Implementable incentives making specified behavior a Bayesian equilibrium are derived whenever the center's information depends stochastically, however slightly, on all relevant private information, and also whenever individuals' relative valuations of acts, however divergent, are not too dissimilarly affected by different states of nature. Feasibility is resolved whenever the desired strategies reveal the agents' beliefs about the center's information. Key concepts of agent similarity are developed for nonresponsive and budget-balancing cases. Copyright 1990 by The Econometric Society.

Seiji Nabeya, Katsuto Tanaka, A General Approach to the Limiting Distribution for Estimators in Time Series Regression with Nonstable Autoregressive Errors, Econometrica, Vol. 58, No. 1 (Jan., 1990), pp. 145-163

This paper reports on an experimental study of-the way in which individuals make inferences from publicly available information. We compare the predictions of a theoretical model of a common knowledge inference process with actual behavior. In the theoretical model, "perfect Bayesians," starting with private information, take actions; an aggregate statistic is made publicly available; the individuals do optimal Bayesian updating and take new actions; and the process continues until there is a common knowledge equilibrium with complete information pooling. We find that the theoretical model roughly predicts the observed behavior, but the actual inference process is clearly less efficient than the standard of the theoretical model, and while there is some pooling, it is incomplete.

Ve consider the problem of designing a contract between a risk-averse agent and a risk-neutral principal when the agent's action is subject to moral hazard and the principal is free to propose a new contract after the agent has chosen his effort level but before the corresponding outcome is revealed.In this setting any optimal contract is equivalent to one that is "renegotiation-proof." A renegotiation-proof contract that induces the agent to choose high effort levels by promising a higher payment following good outcomes must also induce the agent to choose lower effort levels with sufficiently high probability that the contract would not be renegotiated.We show that for a range of utility functions for the agent, including exponential and logarithmic forms, the cost-minimizing renegotiation-proof contract for a given distribution of efforts is the same as the cost-minimizing contract for that distribution under commitment.Thus, the force of the renegotiation-proof constraint is not to change the way that given distributions are implemented, but rather to change which distributions are feasible.However, if the agent has constant relative risk aversion lower than one, the principal may prefer to give the agent an ex-ante rent in order to relax the renegotiation-proofness constraint, so that the optimal contract may differ from, that under commitment not only in the choice of distribution but also in the way that distribution is implemented.Our theory may shed some light on why compensation of managers and contractors is frequently insensitive to the information obtained after the relationship is terminated, and why executives have considerable discretion to adjust the riskiness of their compensation.1.

"This paper estimates semiparametric reduced-form neoclassical models of life-cycle fertility in Sweden.... The estimated model integrates aspects of life cycle fertility that have previously been studied in isolation of each other: completed fertility, childlessness, interbirth intervals, and the time series of annual birth rates. The main objective of this paper is to determine which aspects of life cycle fertility, if any, are sensitive to male income and female wages."

This paper develops an asymptotic theory for residual based tests for cointegration. Attention is given to the augmented Dickey-Fuller (ADF) test and the Z(subscript alpha) and Z(subscript t) unit root tests. Two new tests are also introduced. The tests are shown to be asymptotically similar, and simple representations of their limiting distributions are given and asymptotic critical values are tabulated. The ADF and Z(subscript t) tests are asymptotically equivalent. Power properties of the test are also studied. The tests are consistent if suitably constructed, but the ADF and Z(subscript t) tests have slower rates of divergence under cointegration than the other tests. Copyright 1990 by The Econometric Society.

In this study, the authors report the results from laboratory asset markets designed to test the rational expectations hypothesis that markets aggregate and transmit the information of differentially informed traders. After documenting evidence in favor of the rational expectations model, they examine which features of their environment are necessary or sufficient to achieve an rational expectations equilibrium. The authors find that trading experience and common knowledge of dividends are jointly sufficient to achieve a rational expectations equilibrium, but that neither is a sufficient condition by itself. They also present some stylized facts about the convergence process leading to a rational expectations equilibrium. Copyright 1990 by The Econometric Society.