I study the effect of heterogeneous beliefs about asset prices on the long-term behavior of financial markets. Starting from the ideas of Abreu and Brunnermeier (2003), a two-dimensional system of differential equations is developed. The first dynamic variable is the asset price growth rate. The...

This paper demonstrates how both quantitative and qualitative results of general, analytically tractable asset-pricing model in which heterogeneous agents behave consistently with a constant relative risk aversion assumption can be applied to the particular case of "linear" investment choices....

We consider portfolio selection under nonparametric alpha-maxmin ambiguity in the neighbourhood of a reference distribution. We show strict concavity of the portfolio problem under ambiguity aversion.Implied demand functions are nondifferentiable, resemble observed bid-ask spreads, and are...

A model is presented with counter-cyclical belief heterogeneity and habit-formation preferences. Belief heterogeneity stems from disagreement in the interpretation of common signals. The model accounts for the positive relation between the magnitude of returns and trading volume, the asymmetric...

Since the development of modern portfolio theory (MPT) in the late 1950s and early 1960s, academics have offered numerous competing theories. MPT's simplicity is appealing: The expected return on an asset is simply a function of the return of the market portfolio and the asset's beta to the...

The battle between proponents of the Efficient Markets Hypothesis and champions of behavioral finance has never been more pitched, and little consensus exists as to which side is winning or the implications for investment management and consulting. In this article, I review the case for and...

We develop a model in which investors have heterogeneous beliefs about both the mean and the risk of future signals and the final stock payoff. As investors who perceive the lowest risk vary across different periods, the overall perception of the market risk is reduced in an economy with dynamic...

This paper builds a theoretical framework to endogeneize the editorial decisions of media and analyze their asset pricing implications. The media outlet optimally reports man-bites-dog signals by choosing to report about the firm that generates more uncertainty to investors. There are three main...

Fluctuations in the aggregate balance sheets of financial intermediaries provide a window on the joint determination of asset prices and macroeconomic aggregates. We document that financial intermediary balance sheets contain strong predictive power for future excess returns on a broad set of...