In a model with heterogeneous-risk-aversion agents facing margin constraints, we show how securities' required returns are characterized both by their betas and their margin requirements. Negative shocks to fundamentals make margin constraints bind, lowering risk-free rates and raising Sharpe...

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...

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...

A security's expected return can be decomposed into its "carry" and its expected price appreciation, where carry can be measured in advance without an asset pricing model. We find that carry predicts returns both in the cross section and time series for a variety of different asset classes that...

Human beings want to believe that good outcomes in the future are more likely, but also want to make good decisions that increase average outcomes in the future. We consider a general equilibrium model with complete markets and show that when investors hold beliefs that optimally balance these...

In our incomplete markets economy financial frictions affect the optimal inflation target. Households choose portfolios consisting of risky (uninsurable) capital and money. Money is a bubbly store of value. The market outcome is constrained Pareto inefficient due to a pecuniary externality. Each...