Knowledge that Transforms

In an infinitely repeated version of the Diamond and Dybvig (1983) model, intergenerational transfers enable a bank to achieve interest rate smoothing and to provide depositors with liquidity insurance without Diamond and Dybvig's assumption of no side trades. The bank is subject to runs that may result from either excessive withdrawals or the lack of new deposits. The latter cause, which cannot occur in Diamond and Dybvig's one-generation model, implies that suspension of convertibility may not prevent bank runs. Government intervention may be necessary to maintain bank stability. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.

We show that entrepreneurs may prefer to allow insider trading even when it is not socially optimal. We examine a model in which an insider/manager allocates resources on the basis of his private information and outside information conveyed through the secondary-market price of the firm's shares. If the manager is allowed to trade, he will compete with informed outsiders, reducing the equilibrium quality of outside information. While the benefits to production of outside information are the same for society and entrepreneurs, we show that the social and private costs are different. Thus, entrepreneurs and society may disagree on the conditions under which insider trading restrictions should be imposed.

We consider the multiperiod relationship between a client and a portfolio manager and the resulting problem of motivating a manager of unknown ability to acquire valuable information. We explore the contractual forms and the optimal retention policy of the client and find that the optimal initial set of contracts features a smaller performance-based fee component paid to the manager than in a first-best contract, and the contract choice elicits only partial information about the manager. As a result, ex post performance measurement is critical to future recontracting. In general, managers are retained only if the returns on their portfolio exceed the benchmark by an appropriate amount.

This study examines common stock prices around ex-dividend dates. Such price data usually contain a mixture of observations—some with and some without arbitrageurs and/or dividend capturers active. Our theory predicts that such mixing will result in a nonlinear relation between percentage price drop and dividend yield—not the commonly assumed linear relation. This prediction and another important prediction of theory are supported empirically. In a variety of tests, marginal price drop is not significantly different from the dividend amount. Thus, over the last several decades, one-for-one marginal price drop has been an excellent (average) rule of thumb.

To what extent are the empirical regularities implied by market microstructure theories useful in predicting the short-run behavior of stock returns? A two-equation econometric model of quote revisions and transaction returns is developed and used to identify the relative importance of different microstructure theories and to make predictions. Microstructure variables and lagged stock index futures returns have in-sample and out-of-sample predictive power based on data observed at five-minute intervals. The most striking microstructure implication of the model, confirmed by the empirical results, specifies that the expected quote return is positively related to the deviation between the transaction price and the quote midpoint while the expected transaction return is negatively related to the same variable.

This paper shows that S&P 500 stock betas are overstated and the non–S&P 500 stock betas are understated because of liquidity price effects caused by the S&P 500 trading strategies. The daily and weekly betas of stocks added to the S&P 500 index during 1985–1989 increase, on average, by 0.211 and 0.130. The difference between monthly betas of otherwise similar S&P 500 and non–S&P 500 stocks also equals 0.125 during this period. Some of these increases can be explained by the reduced nonsynchroneity of S&P 500 stock prices, but the remaining increases are explained by the price pressure or excess volatility caused by the S&P 500 trading strategies. I estimate that the price pressures account for 8.5 percent of the total variance of daily returns of a value-weighted portfolio of NYSE/AMEX stocks. The negative own autocorrelations in S&P 500 index returns and the negative cross autocorrelations between S&P 500 stock returns provide further evidence consistent with the price pressure hypothesis.

We analyze the introduction of a nonredundant option, which completes the markets, and the effects of this on information revelation and risk sharing. The option alters the interaction between liquidity and insider trading. We find that the option mitigates the market breakdown problem created by the combination of market incompleteness and asymmetric information. The introduction of the option has ambiguous consequences on the informational efficiency of the market. On the one hand, by avoiding market breakdown, it enables trades to occur and convey information. On the other hand, the introduction of the option enlarges the set of trading strategies the insider can follow. This can make it more difficult for the market makers to interpret the information content of trades and consequently can reduce the informational efficiency of the market. The introduction of the option also has an ambiguous effect on the profitability of insider trades, which can either increase or decrease depending on parameter values.

This article reexamines the autocorrelation patterns of short-horizon stock returns. We document empirical results which imply that these autocorrelations have been overstated in the existing literature. Based on several new insights, we provide support for a market efficiency-based explanation of the evidence. Our analysis suggests that institutional factors are the most likely source of the autocorrelation patterns.

A firm must decide what security to sell to raise external capital to finance a profitable investment opportunity. There is ex ante asymmetry of information regarding the probability distribution of cash flow generated by the investment. In this setting, we derive necessary and sufficient conditions for a security to be optimal (uniquely optimal), that is, for pooling at this security to be an (the unique) equilibrium outcome. Using these conditions we show that the debt contract is (uniquely) optimal if and only if cash flows are ordered by (strict) conditional stochastic dominance. Finally, we derive an equivalence relationship between optimal security designs and designs that minimize mispricing.

Exchange minimum price variation regulations create discrete bid-ask spreads. If the minimum quotable spread exceeds the spread that otherwise would be quoted, spreads will be wide and the number of shares offered at the bid and ask may be large. A cross-sectional discrete spread model is estimated by using intraday stock quotation spread frequencies. The results are used to project $1/16 spread usage frequencies given a $1/16 tick. Projected changes in quotation sizes and in trade volumes are obtained from regression models. For stocks priced under $10, the models predict spreads would decrease 38 percent, quotation sizes would decrease 16 percent, and daily volume would increase 34 percent. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.