We study tradeoffs among active mutual funds' characteristics. In both our equilibrium model and the data, funds with larger size, lower expense ratio, and higher turnover hold more-liquid portfolios. Portfolio liquidity, a concept introduced here, depends not only on the liquidity of the...

We argue that active management's popularity is not puzzling despite the industry's poor track record. Our explanation features decreasing returns to scale: As the industry's size increases, every manager's ability to outperform passive benchmarks declines. The poor track record occurred before...

We empirically analyze the nature of returns to scale in active mutual fund management. We find strong evidence of decreasing returns at the industry level: As the size of the active mutual fund industry increases, a fund's ability to outperform passive benchmarks declines. At the fund level,...

We model optimal fund turnover in the presence of time-varying profit opportunities. Our model predicts a positive relation between an active fund's turnover and its subsequent benchmark-adjusted return. We find such a relation for equity mutual funds. This time-series relation between turnover...

We develop a model of political cycles driven by time-varying risk aversion. Agents choose to work in the public or private sector and to vote Democrat or Republican. In equilibrium, when risk aversion is high, agents elect Democrats—the party promising more redistribution. The model predicts...

We analyze how changes in government policy affect stock prices. Our general equilibrium model features uncertainty about government policy and a government that has both economic and non-economic motives. The government tends to change its policy after performance downturns in the private...

According to conventional wisdom, annualized volatility of stock returns is lower when computed over long horizons than over short horizons, due to mean reversion induced by return predictability. In contrast, we find that stocks are substantially more volatile over long horizons from an...

We develop a general equilibrium model in which stock prices of innovative firms exhibit quot;bubblesquot; during technological revolutions. In the model, the average productivity of a new technology is uncertain and subject to learning. During technological revolutions, the nature of this...

Not necessarily. The fundamental value of a firm increases with uncertainty about average future profitability, and this uncertainty was unusually high in the late 1990s. We calibrate a stock valuation model that includes this uncertainty, and show that the uncertainty needed to match the...

Our simple model features agents heterogeneous in skill and risk aversion, incomplete financial markets, and redistributive taxation. In equilibrium, agents become entrepreneurs if their skill is sufficiently high or risk aversion sufficiently low. Under heavier taxation, entrepreneurs are more...