The dangers of shouting ``fire'' in a crowded theater are well understood, but the dangers of rushing to the exit in the financial markets are more complex. Yet, the two events share several features, and I analyze why people crowd into theaters and trades, why they run, what determines the...

We study three cases in which specialized arbitrageurs lost significant amounts of capital and, as a result, became liquidity demanders rather than providers. The effects on security markets were large and persistent: Prices dropped relative to fundamentals and the rebound took months. While...

This paper derives in closed form the optimal dynamic portfolio policy when trading is costly and security returns are predictable by signals with different mean-reversion speeds. The optimal updated portfolio is a linear combination of the existing portfolio, the optimal portfolio absent...

This Paper solves explicitly a simple equilibrium asset pricing model with liquidity risk – the risk arising from unpredictable changes in liquidity over time. In our liquidity-adjusted capital asset pricing model, a security’s required return depends on its expected liquidity as well as on...

This Paper studies predatory trading: trading that induces and/or exploits other investors’ need to reduce their positions. We show that if one trader needs to sell, others also sell and subsequently buy back the asset. This leads to price overshooting and a reduced liquidation value for the...

We provide a model that links an asset's market liquidity - i.e., the ease with which it is traded - and traders' funding liquidity - i.e., the ease with which they can obtain funding. Traders provide market liquidity, and their ability to do so depends on their availability of funding....

This Paper studies equilibrium asset pricing with liquidity risk (the risk arising from unpredictable changes in liquidity over time). It is shown that the required return on a security depends on its expected illiquidity, the covariances of its own return, illiquidity with market return, and...

We model the demand-pressure effect on prices when options cannot be perfectly hedged. The model shows that demand pressure in one option contract increases its price by an amount proportional to the variance of the unhedgeable part of the option. Similarly, the demand pressure increases the...

Berkshire Hathaway has realized a Sharpe ratio of 0.76, higher than any other stock or mutual fund with a history of more than 30 years, and Berkshire has a significant alpha to traditional risk factors. However, we find that the alpha becomes insignificant when controlling for exposures to...

Any security’s expected return can be decomposed into its “carry” and its expected price appreciation, where carry is a model-free characteristic that can be observed in advance. While carry has been studied almost exclusively for currencies, we find that carry predicts returns both in the...