We build a model of firm-level innovation, productivity growth and reallocation featuring endogenous entry and exit. A new and central economic force is the selection between high- and low-type firms, which differ in terms of their innovative capacity. We estimate the parameters of the model...

The Americans With Disabilities Act (ADA) requires employers to accommodate disabled workers and outlaws discrimination against the disabled in hiring, firing, and pay. Although the ADA was meant to increase employment of the disabled, it also increases costs for employers. The net theoretical...

We develop a dynamic theory of resource wars and study the conditions under which such wars can be prevented. The interaction between the scarcity of resources and the incentives for war in the presence of limited commitment is at the center of our theory. We show that a key parameter...

We provide a general framework for the study of cascade effects created by interconnections between sectors, firms or financial institutions. Focusing on a multi sector economy linked through a supply network, we show how structural properties of the supply network determine both whether...

We extend the basic Schumpeterian endogenous growth model by allowing incumbents to undertake innovations to improve their products, while entrants engage in more "radical" innovations to replace incumbents. Our model provides a tractable framework for the analysis of growth driven by both entry...

When voters fear that politicians may have a right-wing bias or that they may be influenced or corrupted by the rich elite, signals of true left-wing conviction are valuable. As a consequence, even a moderate politician seeking reelection chooses "populist' policies - i.e., policies to the left...

Voters often dismantle constitutional checks and balances on the executive. If such checks and balances limit presidential abuses of power and rents, why do voters support their removal? We argue that by reducing politician rents, checks and balances also make it cheaper to bribe or influence...

We study the evolution of the social norm of "cooperation" in a dynamic environment. Each agent lives for two periods and interacts with agents from the previous and next generations via a coordination game. Social norms emerge as patterns of behavior that are stable in part due to agents'...

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...

To study the short-run and long-run implications on wage inequality, we introduce directed technical change into a Ricardian model of offshoring. A unique final good is produced by combining a skilled and an unskilled product, each produced from a continuum of intermediates (tasks). Some of...