We show that mutual funds contribute to cross-sectional momentum and excess volatility through positive feedback trading. Stocks held by positive feedback funds exhibit much stronger momentum, almost doubling the returns from a simple momentum strategy. This “enhanced” momentum is robust to...

This dissertation consists of four essays exploring how people form beliefs and make decisions in the financial markets and their implications for asset prices. Two common threads run through this dissertation: the persistence of key state variables and the less-than-fully-rational approach to...