Capital Maintenance and Investment: Complements or Substitutes?

This paper studies the properties of demand for capital maintenance services and its interaction with investment under variable capital utilization rate and adjustment costs. The depreciation rate varies with the maintenance effort and the utilization rate of capital. We show that the properties of the demand functions for maintenance services and capital goods depend closely on the sign of the cross derivative of the depreciation function, i.e., on whether the marginal efficiency of maintenance decreases or increases when the rate of capital utilization rises. In our model, it is impossible to reconcile some unquestionable empirical facts and some minimal regularity conditions on the demand function for maintenance services if this cross derivative is positive. In all cases, investment and maintenance are gross complements. Received September 9, 2001; revised version received April 22, 2002 Published online: December 5, 2002 ? Springer-Verlag 2002     

Growth vs. level effect of population change on economic development: An inspection into human-capital-related mechanisms

This paper studies the different mechanisms and the dynamics through which demography is channeled to the economy. We analyze the role of demographic changes in the economic development process by studying the transitional and the long-run impact of both the rate of population growth and the initial population size on the levels of per capita human capital and income. We do that in an enlarged Lucas–Uzawa model with intergenerational altruism. In contrast to the existing theoretical literature, the long-run level effects of demographic changes, i.e. their impact on the levels of the variables along the balanced growth path, are deeply characterized in addition to the more standard long-run growth effects. We prove that the level effect of the population rate of growth is non-negative (positive in the empirically most relevant case) for the average level of human capital, but a priori ambiguous for the level of per capita income due to the interaction of three transmission mechanisms of demographic shocks, a standard one (dilution) and two non-standard (altruism and human capital accumulation). Overall, the sign of the level effects of population growth depends on preference and technology parameters, but numerically we show that the joint negative effect of dilution and altruism is always stronger than the induced positive human capital effect. The growth effect of population growth depends basically on the attitude to intergenerational altruism and intertemporal substitution. Moreover, we also prove that the long-run level effects of population size on per capita human capital and income may be negative, nil, or positive, depending on the relationship between preferences and technology, while its growth effect is zero. Finally, we show that the model is able to replicate complicated time relationships between economic and demographic changes. In particular, it entails a negative effect of population growth on per capita income, which dominates in the initial periods, and a positive effect which restores a positive correlation between population growth and economic performance in the long term.     

Special functions for the study of economic dynamics: The case of the Lucas-Uzawa model

The special functions are intensively used in mathematical physics to solve differential systems. We argue that they should be most useful in economic dynamics, notably in the assessment of the transition dynamics of endogenous economic growth models. We illustrate our argument on the famous Lucas-Uzawa model, which we solve by the means of Gaussian hypergeometric functions. We show how the use of Gaussian hypergeometric functions allows for an explicit representation of the equilibrium dynamics of all variables in level. The parameters of the involved hypergeometric functions are identified using the Pontryagin conditions arising from the underlying optimization problems. In contrast to the pre-existing approaches, our method is global and does not rely on dimension reduction.     

Correction to: The devil is in the details: Capital stock estimation and aggregate productivity growth—An application to the Spanish economy

Portuguese Economic Journal -     

The devil is in the details: Capital stock estimation and aggregate productivity growth—An application to the Spanish economy

Portuguese Economic Journal - The variables that contribute to explaining the major puzzles and paradoxes in macroeconomics and economic growth literature always appear related, directly or...