In this paper, I develop a model to analyze how skill premia differ over time and across countries, and use this model to study the impact of international trade on wage inequality. Skill premia are determined by technology and the relative supply of skills. An increase in the relative supply of...

We examine the concerns that new technologies will render labor redundant in a framework in which tasks previously performed by labor can be automated and new versions of existing tasks, in which labor has a comparative advantage, can be created. In a static version where capital is fixed and...

This essay discusses the effect of technical change on wage inequality. I argue that the behavior of wages and returns to schooling indicates that technical change has been skill-biased during the past sixty years. Furthermore, the recent increase in inequality is most likely due to an...

This paper points out that modeling automation as factor-augmenting technological change has several unappealing implications. Instead, modeling it as the process of machines replacing tasks previously performed by labor is both descriptively realistic and leads to distinct and empirically...

This paper studies the conditions under which the scarcity of a factor (in particular, labor) encourages technological progress and technology adoption. In standard endogenous growth models, which feature a strong scale effect, an increase in the supply of labor encourages technological...

This paper offers a model where firms decide what types of jobs to create and then search for suitable workers. When there are few skilled workers and the productivity gap between the skilled and the unskilled is small, firms create a single type of job and recruit all workers. An increase in...

We extend an analytical general equilibrium model of environmental policy with pre-existing labor tax distortions to include pre-existing monopoly power as well. We show that the existence of monopoly power has two offsetting effects on welfare. First, the environmental policy reduces monopoly...

We assess the concentration and duration of zero tax liabilities and of transfer receipts, using data for households with ten to forty years of observations from the Panel Survey of Income Dynamics. We find that neither is strongly concentrated. Nearly 68% owe no federal tax in at least one...