In macroeconomic models, the elasticity of substitution between clean and dirty energy inputs within the energy aggregate is a central parameter in assessing the necessary conditions for long-run green growth. Using new sectoral data in a panel of 26 countries, we formulate specifications of nested constant elasticity of substitution production functions that allow estimating this parameter for the first time. We present evidence that it significantly exceeds unity, a favorable condition for promoting green growth.

Are structural reforms growth enhancing? Is the effectiveness of reforms constrained by a country's distance from the technology frontier or by its institutional environment? This paper takes a new and comprehensive look at these questions by employing a novel data set that includes several kinds of real (trade, agriculture, and networks) and financial (domestic finance, banking, securities, and capital account) reforms for an extensive list of developed and developing countries, going back to the early 1970s. First-pass evidence based on growth breaks analysis and on panel growth regressions suggests that on average, both real and financial sector reforms are positively associated with higher growth. However, on several occasions, botched reforms resulted in growth disasters. More important, the positive reform-growth relationship is shown to be highly heterogeneous and to be influenced by a country's constraints on the authority of the executive power and by its distance from the technology frontier. Finally, there is some evidence that crises, defined as severe growth downturns, are associated with subsequent reform upticks.

Since Griliches (1969), researchers have been intrigued by the idea that physical capital and skilled labor are more complementary than physical capital and unskilled labor. In this paper we consider the cross-country evidence for capital-skill complementarity using a time-series cross-section panel of 73 developed and less developed countries over a 25-year period. We focus on three empirical issues. First, what is the best specification of the aggregate production technology to address the capital-skill complementarity hypothesis? Second, how should we measure skilled labor? Finally, is there any cross-country evidence in support of the capital-skill complementarity hypothesis? Our main finding is that there is some empirical support for the capital-skill complementarity hypothesis in our macro panel data set.