The optimal portfolio of a utility-maximizing investor trading in the S&P 500 index and cash, subject to proportional transaction costs, becomes stochastically dominated when overlaid with a zero-net-cost portfolio of S&P 500 options bought at their ask and written at their bid price in most...

We propose that financial institutions can act as asset insulators, holding assets for the long run to protect their valuations from consequences of exposure to financial markets. We demonstrate the empirical relevance of this theory for the balance sheet behavior of a large class of...

We provide new empirical evidence suggesting that the marginal investor in mutual funds behaves differently across market conditions. If the marginal investor allocates capital across mutual funds rationally, then the relative performance of funds should be unpredictable. We find however that...

The portfolio flows of institutional investors are widely known to be persistent. What is less well known, however, is the source of this persistence. One possibility is the ?informed trading hypothesis?: that persistence arises from autocorrelated trades of investors who believe they have...

How do macro-financial shocks affect investor behavior and market dynamics? Recent evidence suggests long-lasting effects of personally experienced outcomes on investor beliefs and investment but also significant differences across older and younger generations. We formalize experience-based...

We propose implied spreads (IS) and normalized implied spreads (NIS) as simple measures to characterize option prices. IS is the credit spread of an option's implied bond, the portfolio long a risk-free bond and short a put option. NIS normalizes IS by the risk-neutral default probability and...

This paper develops a dynamic programming model of the optimal refunding strategy and the corresponding value of a callable bond. The model differs from previous work on this subject primarily in that it explicitly admits the possibility of differences between the issuer's expectations of future...

Widespread violations of stochastic dominance by one-month S&P 500 index call options over 1986-2006 imply that a trader can improve expected utility by engaging in a zero-net-cost trade net of transaction costs and bid-ask spread. Although pre-crash option prices conform to the...

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...

We document that the implied volatility skew of S&P 500 index puts is non-decreasing in the disaster index and risk-neutral variance, contrary to the implications of a broad class of no-arbitrage models. The key to the puzzle lies in recognizing that, as the disaster risk increases, customers...