Endogenous Technological Change under Uncertainty

textabstractHow does risk or uncertainty in the productivity of research affect the growth rate of the economy? To answer this question, a model of endogenous technological change is used where sustained growth stems from intentional investments in R&D from profit-maximizing firms. The uncertainty arises from the productivity of these investments in R&D. The main result of this analysis is that the relationship between long-run growth and uncertainty (on the productivity of knowledge creation) depends on two main factors - the returns to scale in knowledge creation (increasing or non-increasing) and the value of the elasticity of intertemporal substitution (higher or lower than some critical value).Based on empirical studies on the returns to scale in knowledge creation ("non-increasing") and the value of the elasticity of intertemporal substitution ("higher than the critical value"), we expect a negative relationship between long-run growth and uncertainty regarding the productivity of knowledge creation