This handbook chapter seeks to document the economic forces that led the US to become an urban nation over its two hundred year history. We show that the urban wage premium in the US was remarkably stable over the past two centuries, ranging between 15 and 40 percent, while the rent premium was...

We develop simple tests for endogenous prices arising from omitted demand factors in discrete choice models. Our approach only requires one to locate testing proxies that have some correlation with the omitted factors when prices are endogenous. We use the difference between prices and their...

Does the mere presence of big banks affect macroeconomic outcomes? In this paper, we develop a theory of granularity (Gabaix, 2011) for the banking sector, introducing Bertrand competition and heterogeneous banks charging variable markups. Using this framework, we show conditions under which...

We study frictions in adjusting earnings to changes in the Social Security Annual Earnings Test (AET) using a panel of Social Security Administration microdata on one percent of the U.S. population from 1961 to 2006. Individuals continue to "bunch" at the convex kink the AET creates even when...

Estimates of the returns to medical care may reflect not only the efficacy of more intensive care, but also unmeasured differences in patient severity or the productivity of health-care providers. We use a variety of instruments that are plausibly orthogonal to heterogeneity among providers as...

Traditional economic models of vaccination assume that agents free-ride on the vaccination decision of others. These models show that private vaccination rates are always below the social optimal and even large subsidies cannot achieve disease eradication. In this paper, we build a model where...

Financial institutions may be vulnerable to predatory short selling. When the stock of a financial institution is shorted aggressively, leverage constraints imposed by short-term creditors can force the institution to liquidate long-term investments at fire sale prices. For financial...

We investigate whether experiencing a natural disaster affects risk-taking behavior. We conduct standard risk games (using real money) with randomly selected individuals in rural Indonesia. We find that individuals who recently suffered a flood or earthquake exhibit more risk aversion....

Uncertainty and its composition can affect the demand for social insurance, and thereby the labor market. This paper shows that small to medium-sized increases in uncertainty or risk aversion are enough to recommend an expansion of the safety net that would be broadly similar to the actual...

If time and effort are required to accurately ascertain the lifetime value of energy efficiency for a durable good, consumers might rationally ignore energy efficiency. This paper argues that such inattention may be rational in the market for automobiles and home appliances. To do so, it...