Knowledge that Transforms

In this article we are concerned with the effect of the number of investment analysts following a firm on the speed of adjustment of the firm’s stock price to new information that has common effects across firms. It is found that returns on portfolios of firms that are followed by many analysts tend to lead those of firms that are followed by fewer analysts, even when the firms are of approximately the same size. Many analyst firms also tend to respond more rapidly to market returns than do few analyst firms, adjusting for firm size. This relation, however, is nonlinear, and the marginal effect of the number of analysts on the speed of price adjustment increases with the number of analysts.

We investigate the informational efficiency of mutual fund performance for the period 1965–84. Results are shown to be sensitive to the measurement of performance chosen. Wefind that returns on S&P stocks, returns on non-S&P stocks, and returns on bonds are significant factors in performance assessment. Once we correct for the impact of non-S&P assets on mutual fund returns, wefind that mutual funds do not earn returns that justify their information acquisition costs. This is consistent with results for prior periods.

We investigate predictability in national equity market returns, and its relation to global economic risks. We show how to consistently estimate the fraction of the predictable variation that is captured by an asset pricing model for the expected returns. We use a model in which conditional betas of the national equity markets depend on local information variables, while global risk premia depend on global variables. We examine single- and multiple-beta models, using monthly data for 1970 to 1989. The models capture much of the predictability for many countries. Most of this is related to time variation in the global risk premia.

For a sample of NYSE firms, we show that wide spreads are accompanied by low depths, and that spreads widen and depths fall in response to bigger volume. Spreads widen and depths fall in anticipation of earnings announcements; these effects are more pronounced for announcements with larger subsequent price changes. Spreads are also wider following earnings announcements, but this effect dissipates quickly after controlling for volume. Collectively, our results suggest liquidity providers are sensitive to changes in information asymmetry risk and use both spreads and depths to actively manage this risk.

A model of trading in speculative markets is developed based on differences of opinion among traders. Our purpose is to explain some of the empirical regularities that have been documented concerning the relationship between volume and price and the time-series properties of price and volume. We assume that traders share common prior beliefs and receive common information but differ in the way in which they interpret this information. Some results are that absolute price changes and volume are positively correlated, consecutive price changes exhibit negative serial correlation, and volume is positively autocorrelated.

I use a new technique to derive a closed-form solution for the price of a European call option on an asset with stochastic volatility. The model allows arbitrary correlation between volatility and spotasset returns. I introduce stochastic interest rates and show how to apply the model to bond options and foreign currency options. Simulations show that correlation between volatility and the spot asset’s price is important for explaining return skewness and strike-price biases in the Black-Scholes (1973) model. The solution technique is based on characteristic functions and can be applied to other problems. Many plaudits have been aptly used to describe Black and Scholes ’ (1973) contribution to option pricing theory. Despite subsequent development of option theory, the original Black-Scholes formula for a European call option remains the most successful and widely used application. This formula is particularly useful because it relates the distribution of spot returns I thank Hans Knoch for computational assistance. I am grateful for the suggestions of Hyeng Keun (the referee) and for comments by participants

[We explore the dynamics of a takeover bid. In contrast to preceding models, if the initial takeover bid is unsuccessful a raider is allowed to make a new tender offer in order to try and secure the remaining shares. Numerical analysis shows that the raider's tender offer rises over time as he accumulates more shares. The anticipation of a higher tender offer in the future makes shareholders more inclined to hold their shares and forces the raider to offer a higher premium than is predicted by static theories. As the time between tender offers goes to zero, we show analytically that the expected profit from engaging in a takeover goes to zero.]

[We characterize a credit market equilibrium in which banks coexist with capital markets and firms obtain funding from both sources. An incentive problem exists between the firm's insiders and outside providers of capital. Banks can provide not only credit but also monitoring services. We show that when banks cannot precommit to a particular level of monitoring, there is a unique credit market equilibrium with firms being financed with a combination of bank credit and external capital. In this equilibrium, a marginal substitution of bank credit for capital market financing would raise the firm's stock price.]

[In Japan, almost identical government bonds can trade at large price differentials. Motivated by this phenomenon, we examine the issue of the value of liquidity in markets for riskless securities. We develop a model of an issuer of bonds, a market maker, and heterogeneous investors trading in an incomplete market. We show not only that divergent prices for similar securities can be sustained in a rational expectations equilibrium, but also that this divergence may be optimal from the perspective of the issuer. Price segmentation is possible because agents have a desire to trade, but short-sale restrictions limit their trading strategies and prevent them from forcing bond prices to be equal. Restricting the form of market making to exclude price competition and unregulated profit maximization is also necessary to sustain price segmentation. The optimality of segmentation from the issuer's standpoint arises because of the issuer's ability to charge for the liquidity services provided to the investors.]

[There is substantial evidence that insider trading is present around corporate announcements and that this insider trading is motivated by private information. Using real estate investment trusts that choose to reappraise themselves as our sample, we establish that the appraisals contain information, but find no market response to the public announcement of this information in these appraisals. We consider two possible explanations for this inconsistency: the first that the appraisal information is not highlighted in earnings reports and hence remains unobserved; and the second that insiders trade on the appraisal information in the time that elapses between the appraisal and its public announcement. We find strong support for the second hypothesis, with insiders buying (selling) after they receive favorable (unfavorable) appraisal news, especially for negative appraisals. We also find that positive (negative) appraisals and net insider buying (selling) elicit significant positive (negative) abnormal returns during the appraisal period.]