Research Interests

I have devoted the bulk of my career to building mathematical models that shed light on a variety of economic and social phenomena such as economic fluctuations, the nature of oligopolistic competition, the growth of cities, informal economic activity, and the spatial distribution of crime. I have also developed new statistical tools for analyzing economic and financial data. Recently, I have been particularly interested in asset prices. With Lars Hansen, I have been building tools to study long-run risks in financial markets. With colleagues at the Bendheim Center of Finance at Princeton University, I have studied the role of disagreement on the precision of information, together with the costs related to short-selling, in sustaining asset-price bubbles and the associated excessive trading. We have also proposed analogous models concerning the emergence and implosion of bubbles.

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Primary Section

Section 54: Economic Sciences