Volume 10, Issue 4

We show for a class of basic growth models that convergence in ratios does not imply the pathwise convergence to the corresponding balanced growth path in the state space. We derive conditions on parameters and on the elasticity of the savings function for convergence or divergence and apply our results to the Solow model, an augmented Solow model as well as to an optimal growth model. An implication for the convergence debate is that two economies that differ only in the initial capital stock and converge in per capita terms might diverge to infinity in absolute terms.

The optimal order of extracting resource deposits of unknown size depends on the informational characteristics of the extraction process. This paper fills the gap between two strands of literature. The first strand is about the optimal extraction of single reserve under stock-size uncertainty. The second strand is about the optimal order of extraction of deposits of known sizes. Our emphasis on the premium for resolution of uncertainty complements Solow and Wan’s shadow surcharge when extraction moves from a low-cost deposit to a high-cost one.

This paper examines the effects of aggregate factor income risk in a tractable version of the stochastic Romer endogenous growth model. Labor supply is endogenous. The presence of labor income risk unambiguously increases savings and growth due to precautionary motives. Households not only underaccumulate but also work less along the balanced growth path of the competitive economy when compared with the Pareto-efficient allocation. The paper also discusses distributive disturbances for the case of inelastic labor supply. Here, growth effects are negative for empirically plausible correlations of the underlying shocks.

We combine the augmented Solow model with the Mincer equation to derive a specification that identifies an education externality within a production function framework. The previous empirical literature has not reached a consensus about the size of the education externality, which is given by the difference between the microeconomic and the macroeconomic return to education. Relative to our benchmark value that is based on a parameterization of the derived specification, we find that the estimated education externality is too large when the empirical model is not properly restricted, and appears to be absent when all control variables of the empirical model are properly accounted for. We note that the absence of an education externality is difficult to reconcile with observed levels of education subsidies for efficiency reasons.

We analyze a generalized neoclassical growth model that combines a normalized CES production function and possible asymmetries of savings out of factor incomes. This generalized model helps to shed new light on a recent debate concerning the impact of factor substitution and income distribution on economic growth. We show that this impact relies on both an efficiency and a distribution effect, where the latter is caused by the distributional consequences of an increase in the elasticity of substitution. While the efficiency effect is always positive, the sign of the distribution effect depends on the particular savings hypothesis. If the savings rate out of capital income is substantial so that a certain threshold value is surpassed, the efficiency effect dominates and higher factor substitution accelerates the accumulation of capital and works as a major engine of growth.