Knowledge that Transforms

Abstract This paper takes a new look at the predictability of stock market returns with risk measures. We find a significant positive relation between average stock variance (largely idiosyncratic) and the return on the market. In contrast, the variance of the market has no forecasting power for the market return. These relations persist after we control for macroeconomic variables known to forecast the stock market. The evidence is consistent with models of time‐varying risk premia based on background risk and investor heterogeneity. Alternatively, our findings can be justified by the option value of equity in the capital structure of the firms.

Abstract Trading volume of infinitely lived securities, such as equity, is generically zero in Lucas asset pricing models with heterogeneous agents. More generally, the end‐of‐period portfolio of all securities is constant over time and states in the generic economy. General equilibrium restrictions rule out trading of equity after an initial period. This result contrasts the prediction of portfolio allocation analyses that portfolio rebalancing motives produce nontrivial trade volume. Therefore, other causes of trade must be present in asset markets with large trading volume.

This paper analyzes the early exercise of exchange‐traded options by different classes of investors over the 1996 to 1999 period. A large number of exercises are identified as clearly irrational without invoking any model of market equilibrium. Customers of discount brokers and customers of fullservice brokers both engage in a significant number of irrational exercises while traders at large investment houses exhibit no irrational early exercise behavior. Rational and irrational exercise is triggered for discount and full‐service customers by the underlying stock price attaining its highest level over the past year and by high returns on the underlying stock.

ABSTRACT We argue that short sellers affect prices in a significant and systematic manner. In particular, we contend that speculative short sales contribute to the weekend effect: The inability to trade over the weekend is likely to cause these short sellers to close their speculative positions on Fridays and reestablish new short positions on Mondays causing stock prices to rise on Fridays and fall on Mondays. We find evidence in support of this hypothesis based on a comparison of high short‐interest stocks and low short‐interest stocks, stocks with and without actively traded options, IPOs, zero short‐interest stocks, and highly volatile stocks.

ABSTRACT This paper derives preference‐free option pricing equations in a discrete time economy where asset returns have continuous distributions. There is a representative agent who has risk preferences with an exponential representation. Aggregate wealth and the underlying asset price have transformed normal distributions which may or may not belong to the same family of distributions. Those pricing results are particularly valuable (a) to show new sufficient conditions for existing risk‐neutral option pricing equations (e.g., the Black‐Scholes model), and (b) to obtain new analytical solutions for the price of European‐style contingent claims when the underlying asset has a transformed normal distribution (e.g., a negatively skew lognormal distribution).

ABSTRACT Incentive fees for money managers are frequently accompanied by high‐water mark provisions that condition the payment of the performance fee upon exceeding the previously achieved maximum share value. In this paper, we show that hedge fund performance fees are valuable to money managers, and conversely, represent a claim on a significant proportion of investor wealth. The high‐water mark provisions in these contracts limit the value of the performance fees. We provide a closed‐form solution to the cost of the high‐water mark contract under certain conditions. Our results provide a framework for valuation of a hedge fund management company.

ABSTRACT Green and Hollifield (1992) argue that the presence of a dominant factor would result in extreme negative weights in mean‐variance efficient portfolios even in the absence of estimation errors. In that case, imposing no‐short‐sale constraints should hurt, whereas empirical evidence is often to the contrary. We reconcile this apparent contradiction. We explain why constraining portfolio weights to be nonnegative can reduce the risk in estimated optimal portfolios even when the constraints are wrong. Surprisingly, with no‐short‐sale constraints in place, the sample covariance matrix performs as well as covariance matrix estimates based on factor models, shrinkage estimators, and daily data.

We develop a contracting model between shareholders and managers in which managers diversify their firms for two reasons: to reduce idiosyncratic risk and to capture private benefits. We test the comparative static predictions of our model. In contrast to previous work, we find that diversification is positively related to managerial incentives. Further, the link between firm performance and managerial incentives is weaker for firms that experience changes in diversification than it is for firms that do not. Our findings suggest that managers diversify their firms in response to changes in private benefits rather than to reduce their exposure to risk.

We examine security analysts' career concerns by relating their earnings forecasts to job separations. Relatively accurate forecasters are more likely to experience favorable career outcomes like moving up to a high‐status brokerage house. Controlling for accuracy, analysts who are optimistic relative to the consensus are more likely to experience favorable job separations. For analysts who cover stocks underwritten by their houses, job separations depend less on accuracy and more on optimism. Job separations were less sensitive to accuracy and more sensitive to optimism during the recent stock market mania. Brokerage houses apparently reward optimistic analysts who promote stocks.

Abstract This paper examines whether higher order multifactor models, with state variables linked solely to underlying LIBOR‐swap rates, are by themselves capable of explaining and hedging interest rate derivatives, or whether models explicitly exhibiting features such as unspanned stochastic volatility are necessary. Our research shows that swaptions and even swaption straddles can be well hedged with LIBOR bonds alone. We examine the potential benefits of looking outside the LIBOR market for factors that might impact swaption prices without impacting swap rates, and find them to be minor, indicating that the swaption market is well integrated with the LIBOR‐swap market.