We model the relationship between asset float (tradeable shares) and speculative bubbles. Investors with heterogeneous beliefs and short-sales constraints trade a stock with limited float because of insider lockups. A bubble arises as price overweighs optimists' beliefs and investors anticipate...

Kilauea volcano is the largest stationary source of SO2 pollution in the United States of America. Moreover, the SO2 that the volcano emits eventually forms particulate matter, another major pollutant. We use this exogenous SO2 on emergency room admissions and costs in the state of Hawaii....

Consider two random variables X and Y. In initial probability and statistics courses, a discussion of various concepts of dissociation between X and Y is customary. These concepts typically involve independence and uncorrelatedness. An example is shown where E(Y^n|X) = E(Y^n) and E(X^n|Y) =...

This paper studies inference in a continuous-time game where an agent’s decision to quit an activity depends on the participation of other players. In equilibrium, similar actions can be explained not only by direct influences, but also by correlated factors. Our model can be seen as a...

This paper investigates the determinants of informal economic activity. We present two equilibrium models of informality and test their implications using a survey of 48,000+ small firms in Brazil. We define informality as tax avoidance; firms in the informal sector avoid tax payments but suffer...

This paper studies the identification of a simultaneous equation model where the variable of interest is a duration measure. It proposes a game theoretic model in which durations are determined by strategic agents. In the absence of strategic motives, the model delivers a version of the...

extra-marital affairs.