Knowledge that Transforms

This paper develops a model based on Schumpeter's process of creative destruction. It departs from existing models of endogenous growth in emphasizing obsolescence of old technologies induced by the accumulation of knowledge and the resulting process or industrial innovations. This has both positive and normative implications for growth. In positive terms, the prospect of a high level of research in the future can deter research today by threatening the fruits of that research with rapid obsolescence. In normative terms, obsolescence creates a negative externality from innovations, and hence a tendency for laissez-faire economies to generate too many innovations, i.e too much growth. This business-stealing effect is partly compensated by the fact that innovations tend to be too small under laissez-faire. The model possesses a unique balanced growth equilibrium in which the log of GNP follows a random walk with drift. The size of the drift is the average growth rate of the economy and it is endogenous to the model ; in particular it depends on the size and likelihood of innovations resulting from research and also on the degree of market power available to an innovator.

The author considers fair division when monetary compensations are feasible and utilities are quasi-linear. Four axioms are discussed: individual rationality, resource monotonicity, population solidarity, and the stand alone test. The latter views the utility from consuming all the goods as an upper bound on every coalition's actual (joint) utility. Under efficiency, the four axioms show little compatibility. However, when the goods have enough substitutability in everyone's preferences, the Shapley value of the surplus sharing game satisfies all four axioms. An example is the optimal assignment of indivisible goods when every agent consumes only one good. Copyright 1992 by The Econometric Society.

This paper presents a new approach to organizing universal health insurance. First, the government divides the entire population into many large groups. Then, the government creates a federal health insurance system (HealthFed), modeled on the Federal Reserve System, to fill the role now played by the benefits office of a large firm. The HealthFed would create a short menu of alternatives, solicit bids for insuring the entire group, and price alternatives. There would be redistribution between groups and pricing of alternatives to reflect optimal social insurance principles. There would be no connection between health insurance and employment. Copyright 1992 by The Econometric Society.

This paper tests the separation of farm labor supply and labor demand decisions, using the observation that household composition is an important determinant of farm labor use with nonseparation. After assessing the conditions under which the test has power against several alternatives, an empirical model is developed to test the proposition that farm employment is independent of family composition. The model is estimated on a data set from rural Java. The null hypothesis that farm labor allocation decisions are independent of household structure is not rejected. The results are robust to different specifications of the labor demand function. Copyright 1992 by The Econometric Society.

The authors show that the CUSUM test of the stability over time of the coefficients of a linear regression model, which is usually based on recursive residuals, can also be applied to ordinary least squares residuals. The authors derive the limiting null distribution of the resulting test and compare its local power to that of the standard procedure. It turns out that neither version is uniformly superior to the other. Copyright 1992 by The Econometric Society.

Suppose two agents play a game, each using a computable algorithm to decide what to do, these algorithms being common knowledge. The author shows that it is possible to act rationally provided he limits his attention to a natural subset of solvable games and to opponents who use rational algorithms; the outcome is a Nash equilibrium. Going further, the author shows that rationality is possible on many domains of games and opposing algorithms but each domain requires a particular solution algorithm; no one algorithm is rational on all possible domains. Copyright 1992 by The Econometric Society.

This paper considers the effect of an airline's scale of operation at an airport on the profitability of routes flown out of that airport. The empirical methodology uses the entry decisions of airlines as indicators of underlying profitability; the results extend the empirical literature on airport presence by providing a new set of estimates of the determinants of city-pair profitability. These estimates imply that city-pair profits increase in airport presence and decrease rapidly in the number of entering firms. The literature on empirical models of oligopoly entry is also extended via a focus on the role of differences between firms. Copyright 1992 by The Econometric Society.

The authors investigate the implementation of social choice functions that map to lotteries over alternatives. They require virtual implementation in iteratively undominated strategies. Under very weak domain restrictions, they show that if there are three or more players, any social choice function may be so implemented. The literature on implementation in Nash equilibrium and its refinements is compromised by its reliance on game forms with unnatural features (for example, "integer games") or "modulo" constructions with mixed strategies arbitrarily excluded. In contrast, the authors' results employ finite (consequently "well-behaved") mechanisms and allow for mixed strategies. Copyright 1992 by The Econometric Society.

This paper provides an extension of Savage's subjective expected utility theory for decisions under uncertainty. It includes in the set of events both unambiguous events for which probabilities are additive as well as ambiguous events for which probabilities are permitted to be nonadditive. The main axiom is cumulative dominance which adapts stochastic dominance to decision making under uncertainty. We derive a Choquet expected utility representation and show that a modification of cumulative dominance leads to the classical expected utility representation. The relationship of our approach with that of Schmeidler who uses a two-stage formulation to derive Choquet expected utility is also explored.

This paper develops a two-sector overlapping-generations model. It characterizes the dynamical system globally and establishes sufficient conditions for the existence of a globally unique perfect-foresight equilibrium. It provides, therefore, a useful framework for global dynamic analysis of phenomena whose modeling requires a multidimensional commodity space. The analysis demonstrates that gross substitutability in consumption is not sufficient for the determinacy of equilibrium in this production economy. However, if in addition the investment good is capital intensive and second period consumption of two-period-lived individuals is a normal good, then the perfect-foresight equilibrium is globally unique. Copyright 1992 by The Econometric Society.