This paper analyzes the dependence of average consumption on the saving rate in a one-sector neoclassical Solow growth model with production shocks and stochastic rates of population growth and depreciation where arbitrary ergodic processes are considered. We show that the long-run behavior of the stochastic capital intensity, and hence average consumption along any sample path, is uniquely determined by a random fixed point that depends continuously on the saving rate. This result enables us to prove the existence of a golden-rule saving rate that maximizes average consumption per capita. We also show that the golden-rule path is dynamically efficient. The results are illustrated numerically for Cobb–Douglas and CES production functions.

The lack of a supranational legal authority that can enforce private contracts across borders makes debt repayment in an international setting contingent on borrowers' willingness to pay rather than ability to pay. This market failure (i.e., inadequate enforcement) causes investment to fall short of its unconstrained level. This paper examines how foreign aid affects a country's willingness to honor private investment agreements. We consider two types of aid: technical assistance and loan subsidies. We show that when enforcement is inadequate, aid has the following effects: (i) it reduces default risk, promotes capital flows, and can, in principle, restore investment to its unconstrained level; (ii) when default risk is high, aid can increase the welfare of both the recipient and the donor country. Thus, foreign aid serves as an enforcement mechanism in an international setting. This provides a nonaltruistic rationale for foreign aid. Finally, we discuss the implications of providing bilateral versus multilateral aid (e.g., by individual countries versus multilateral organizations).

This paper investigates the impact of anticipated inflation on features of the business cycle in the presence of recursive but intertemporally dependent tastes. Intertemporal dependence is induced by the presence of a variable or endogenous individual rate of time preference. Quantitative experiments indicate that variability in the rate of time preference can enhance the contribution of monetary shocks to the fluctuations of real variables. Another implication of the variable-time-preference model is that, unlike the fixed time preference model, the business cycle features in high inflation and low inflation economies can be very different. The contribution of monetary shocks to fluctuations increases partly because endogenous time preference accentuates inflation-tax effects, which are already present in the standard framework because of the presence of cash-in-advance constraints. The change in the relative role of monetary shocks is also related to how variable time preference alters the effects of technology shocks, which can be quantitatively or qualitatively different in comparison to the standard model, depending on the parameters of the model.

If one drops the strong assumption that firms and households know all of the relevant parameters, and instead models agents as learning these parameters, the estimated parameters become random variables. Taking expectations several periods into the future may then involve taking the expectation of a product of random variables. Because the resulting problem is difficult, previous research has avoided it. This paper makes some progress using both analytical and numerical techniques. Focusing especially on consumption, we find that the resulting covariance terms could account for the well-documented empirical result that consumption displays excess sensitivity to lagged income. We show that a similar covariance effect could play a role in many widely used economic models.

This paper attempts to derive several economic conservation laws and to test the validity of the optimal growth models using the income/wealth ratios for the United States, Japan, and other OECD countries. Conservation laws vary with the type of the objective function depicted, such as the maximization of the aggregate consumption or the maximization of per-capita consumption. The operational concept of “wealth-like quantity” is identified, although the Goldsmith-Kendrick standard definition of “net national wealth” should not always be used. The last section of the paper takes up an empirical analysis to determine how different economies have achieved long-term (optimal) growth. The U.S. economy has been operating rather efficiently, whereas the Japanese economy, after the oil shocks of the 1970's, has behaved differently, leading into the bubble period of the early 1990's.

Building on a nonlinear additively separable representation for the generator of preferences, this article provides an extensive characterization of intertemporal consumption—leisure arbitrages with an endogenous measure of impatience. A joint characterization of the comparative dynamics of consumption and leisure is undertaken. An analytical approach first puts in evidence a classical Slutsky decomposition between revenue and substitution effects after various perturbations. Those conclusions are at a second stage illustrated by a three-dimensional geometric argument.