Knowledge that Transforms

Several recent studies have suggested that empirical rejections of the permanent income/life cycle model might be due to the existence of liquidity constraints. This paper tests the permanent income hypothesis against the alternative hypothesis that consumers optimize subject to a well-specified sequence of borrowing constraints. Implications for consumption in the presence of borrowing constraints are derived and then tested using time-series/cross-section data on families from the Panel Study of Income Dynamics. The results generally support the hypothesis that an inability to borrow against future labor income affects the consumption of a significant portion of the population.

Liberal political philosophy, represented classically by John Locke and today by libertarians, defends great inequality of economic outcome on the basis that people own themselves and are entitled to establish private property in the external world by virtue of that self-ownership. Contemporary nonlibertarian political philosophers, such as John Rawls and Ronald Dworkin, achieve their relatively egalitarian conclusion by effectively denying self-ownership as a premise. An alternative challenge to liberalism, which does not take the radical starting point of denying self-ownership, is to declare that while certain rights to benefit by virtue of superior skill should be protected (a degree of self-ownership), productive assets in the external world be viewed as publicly owned and not privately appropriable. What allocation mechanisms on a space of possible economies satisfy axioms that are necessary to guarantee both private ownership of self and public or joint ownership of the external world? We propose an axiomatic method for modeling problems in political philosophy of this sort and answer the question posed for a simple model. The result shows that the degree of inequality defended by neo-Lockeanism can be challenged without denying, a priori, self-ownership, its relatively attractive postulate.

Despite the widespread belief that entrepreneurship is a key factor in economic development, there have been few attempts to develop formal models to analyze the phenomenon. This paper presents a model in which endogenous entrepreneurial activity is a key determinant of economic growth. The theory also differs from standard models in that growth is driven by the imitative activities of entrepreneurs. Previous theories have focused on the direct production of knowledge, underemphasizing the importance of imitation in the growth process. The paper also examines external effects arising from these entrepreneurial activities--effects distinct from those studied by Paul Romer.

A theoretical analysis of "optimal" (Nash equilibrium) tariff rates is presented. A numerical general equilibrium model is then used to find Nash equilibrium tariff rates for the United States and Canada. The Nash equilibrium tariffs are small relative to partial equilibrium estimates: 18 percent for the United States and 6 percent for Canada. The United States is essentially indifferent between the Nash equilibrium and free trade, while Canada is better off at the latter by $4 billion. Empirical results support theoretical predictions that the optimal tariff is smaller when the country is smaller, there are scale economies and free entry, and capital is internationally mobile.

The paper develops new methodology for the estimation of prewar GNP, taps previously unused data sources, and develops new estimates for the periods 1869-1908 and 1869-1928. Primary among the new data sources are direct measures of output in the transportation, communications, and construction sectors and estimates of the consumer price index. New measures of real GNP, nominal GNP, and the GNP deflator are developed. The new estimates of real GNP are as volatile on average over the business cycle as the traditional Kuznets-Kendrick series but dampen the amplitude of some cycles while raising the amplitude of others. The new estimates of the GNP deflator are distinctly less volatile than the traditional series and in fact no more volatile than those in the postwar period.

Gary Becker's "Rotten Kid theorem" asserts that if all family members receive gifts of money income from a benevolent household member, then even if the household head does not precommit to an incentive plan for family members, it will be in the interest of selfish family members to maximize total family income. I show by examples that the Rotten Kid theorem is not true without assuming transferable utility. I find a simple condition on utility functions that is necessary and sufficient for there to be the kind of transferable utility needed for a Rotten Kid theorem. While restrictive, these conditions still allow one to apply the strong conclusions of the Rotten Kid theorem in an interesting class of examples.

This paper describes two models of an agency that is collecting and reporting observations on a dynamical linear stochastic economy. The first is a "classical" model, with the agency reporting data that are the sum of a vector of "true" variables and a vector of measurement errors that are orthogonal to the true variables. The second is a model of an agency that uses an optimal filtering method to construct least-squares estimates of the true variables. These two models of the reporting agency imply different likelihood functions. A model of the investment accelerator is used as an example to illustrate the differing implications of the models.

This paper studies reputation formation and the evolution over time of the incentive effects of reputation to mitigate conflicts of interest between borrowers and lenders. Borrowers use the proceeds of their loans to fund projects. In the absence of reputation effects, borrowers have incentives to select excessively risky projects. If there is sufficient adverse selection, reputation will not initially provide improved incentives to borrowers with short credit histories. Over time, if a good reputation is acquired, reputation will provide improved incentives. General characteristics of markets in which reputation takes time to work are identified.

Though it is always mentioned first among the list of obvious manias, no serious effort has ever been expended to investigate the market fundamentals that might have driven the tulip speculation. This paper compiles time series on individual tulip prices and examines market fundamentals potentially driving prices. Most of the "tulipmania" was not obvious madness. High but rapidly depreciating prices for rare bulbs is a typical pattern in the flower bulb industry. Only the last month of the speculation, during which common bulb prices increased rapidly and crashed, remains as a potential bubble.