We develop a model of portfolio choice capable of nesting the views of Keynes, advocating concentration in a few familiar assets, and Markowitz, advocating diversification across all available assets. In the model, the return distributions of risky assets are ambiguous, and investors are averse...

Our objective is to understand the trading strategy that would allow an investor to take advantage of quot;excessivequot; stock price volatility and quot;sentimentquot; fluctuations. We construct a general equilibrium model of sentiment. In it, there are two classes of agents and stock prices...

Our objective is to identify the trading strategy that would allow an investor to take advantage of excessive stock price volatility and sentiment fluctuations. We construct a general-equilibrium model of sentiment. In it, there are two classes of agents and stock prices are excessively volatile...