This paper analyzes an important class of models in which expectations play an important role. Topics included in the analysis are tests of: (1) rationality of forecasts in either market or survey data, (2) capital market efficiency, (3) the short-run neutrality of monetary policy and, (4)...

Movements in asset prices are a major risk confronting individuals. This paper establishes new asset pricing results when agents differ in risk preference, time preference and/or expectations. It shows that risk tolerance is a critical concept driving savings decisions, consumption allocations,...

This paper presents a simple general equilibrium model of asset pricing in which profitable informed trading can occur without any "noise" added to the model. It shows that models of profitable informed trading must restrict the portfolio choices of uninformed traders: in particular, they cannot...

This paper explores two perspectives on the rational expectations hypothesis. One perspective is that of economic agents in such a model, who form inferences about the future using probabilities implied by the model. The other is that of an econometrician who makes inferences about the...

A plot of expected returns versus betas obeys virtually no relation to an inefficient index portfolio's mean-variance location. If the index portfolio is inefficient, then the coefficients and R- squared from an ordinary-least-squares regression of expected returns on betas can equal essentially...

Many seemingly discordant results are reconciled if firm-specific return volatility is characterized as the intensity with which firm-specific events occur. A functionally efficient stock market allocates capital to its highest value uses, which often amounts to financing Schumpeterian creative...

Anomalies are empirical results that seem to be inconsistent with maintained theories of asset-pricing behavior. They indicate either market inefficiency (profit opportunities) or inadequacies in the underlying asset-pricing model. The evidence in this paper shows that the size effect, the value...

Motivated by psychological evidence that attention is a scarce cognitive resource, we model investors' attention allocation in learning and study the effects of this on asset-price dynamics. We show that limited investor attention leads to ``category-learningquot; behavior, i.e., investors tend...

Most previous research tests market efficiency and asset pricing models using average abnormal trading profits on dynamic trading strategies, and typically rejects the joint hypothesis. In contrast, we measure the ability of a simple risk model and the efficient-market hypothesis to explain the...