Commentaries on the credit bubble of 2003-2007 routinely equate it with earlier episodes like the Internet boom. While credits were over-priced like Internet stocks a decade before, we show, using a model based on disagreement and short-sales constraints, that this is where the similarity ends....

We present an extrapolative model of bubbles. In the model, many investors form their demand for a risky asset by weighing two signals—an average of the asset's past price changes and the asset's degree of overvaluation. The two signals are in conflict, and investors “waver” over time in...

Recent experience has given rise to the financialization view: increased trading in commodity fu­tures markets leads to an increase in the level and volatility of spot prices. We construct a large panel data set which includes commodities with and without futures markets. The data do not...

A number of theories have been proposed to explain the medium-term momentum in stock returns identified by Jegadeesh and Titman (1993). We test one such theory--based on the gradual-information-diffusion model of Hong and Stein (1997)--and establish three key results. First, once one moves past...

A surprisingly large amount of commentary today marks the beginning of the dot-com bubble of the late 1990s from either the Netscape Communications initial public offering of 1995 or Alan Greenspan's quot;irrational exuberancequot; speech of 1996. We believe that this is wrong: we see little...

We introduce diagnostic expectations into a standard setting of price formation in which investors learn about the fundamental value of an asset and trade it. We study the interaction of diagnostic expectations with two well-known mechanisms: learning from prices and speculation (buying for...

I analyze an extension of the New Keynesian model that features overlapping generations of finitely-lived agents and (stochastic) transitions to inactivity. In contrast with the standard model, the proposed framework allows for the existence of rational expectations equilibria with asset price...

Creative destruction not only involves bringing new technology to market, it imposes higher risk on the future of existing assets. We characterize the asset pricing implications of creative destruction when investors compete for market share. Compared to the social optimum, the quest for...

We propose a dynamic heterogeneous agents model which generates testable hypotheses about the formation, timing and bursting of asset price bubbles in the presence of short-sale constraints, given a calibration that is consistent with momentum and reversal effects for unconstrained assets....

This paper uses three different sources of data to investigate the association between the business cycle--measured with unemployment rates--and environmental concern. Building on recent research that finds internet search terms to be useful predictors of health epidemics and economic activity,...