Knowledge that Transforms

We evaluate predictive regressions that explicitly consider the time-variation of coefficients in a comprehensive Bayesian framework. For monthly returns of the S&P 500 index, we demonstrate statistical as well as economic evidence of out-of-sample predictability: relative to an investor using the historic mean, an investor using our methodology could have earned consistently positive utility gains (between 1.8% and 5.8% per year over different time periods). We also find that predictive models with constant coefficients are dominated by models with time-varying coefficients. Finally, we show a strong link between out-of-sample predictability and the business cycle.

The sensitivity of stock options' payoff to return volatility, or vega, provides risk-averse CEOs with an incentive to increase their firms' risk more by increasing systematic rather than idiosyncratic risk. This effect manifests because any increase in the firm's systematic risk can be hedged by a CEO who can trade the market portfolio. Consistent with this prediction, we find that vega gives CEOs incentives to increase their firms' total risk by increasing systematic risk but not idiosyncratic risk. Collectively, our results suggest that stock options might not always encourage managers to pursue projects that are primarily characterized by idiosyncratic risk when projects with systematic risk are available as an alternative.

We study the relative and absolute pricing of CMBX contracts (commercial real estate derivatives) during the recent financial crisis. Using a structural CMBX pricing model, we find little systematic mispricing relative to REIT equity and options. We do find short-term deviations from this relative pricing relationship that are statistically and economically significant. In particular, the CMBX market temporarily overreacts to news announcements. We provide evidence that this temporary mispricing is caused by price pressure due to hedging activities. Finally, an absolute pricing analysis provides no substantial evidence that CMBX contracts traded at fire sale levels during the crisis.

We study asset-pricing implications of innovation in a general-equilibrium overlapping-generations economy. Innovation increases the competitive pressure on existing firms and workers, reducing the profits of existing firms and eroding the human capital of older workers. Due to the lack of inter-generational risk sharing, innovation creates a systematic risk factor, which we call “displacement risk.” This risk helps explain several empirical patterns, including the existence of the growth-value factor in returns, the value premium, and the high equity premium. We assess the magnitude of displacement risk using estimates of inter-cohort consumption differences across households and find support for the model.

We use a well-developed dynamic panel generalized method of moments (GMM) estimator to alleviate endogeneity concerns in two aspects of corporate governance research: the effect of board structure on firm performance and the determinants of board structure. The estimator incorporates the dynamic nature of internal governance choices to provide valid and powerful instruments that address unobserved heterogeneity and simultaneity. We re-examine the relation between board structure and performance using the GMM estimator in a panel of 6,000 firms over a period from 1991 to 2003, and find no causal relation between board structure and current firm performance. We illustrate why other commonly used estimators that ignore the dynamic relationship between current governance and past firm performance may be biased. We discuss where it may be appropriate to consider the dynamic panel GMM estimator in corporate governance research, as well as caveats to its use.

This paper investigates the determinants of the compensation structure for brokers who advise customers regarding the suitability of financial products. Our model explains why brokers are commonly compensated indirectly through contingent commissions paid by product providers, even though this compensation structure could lead to biased advice. When customers are wary of the adviser's incentives, contingent commissions can be an effective incentive tool to induce the adviser to learn which specialized product is most suitable for the specific needs of customers. If, instead, customers naively believe they receive unbiased advice, high product prices and correspondingly high commissions become a tool of exploitation. Policy intervention that mandates disclosure of commissions can protect naive consumers and increase welfare. However, prohibiting or capping commissions could have the unintended consequence of stifling the adviser's incentive to acquire information. More vigorous competition benefits consumers and reduces exploitation, but firms have limited incentives to educate naive customers.

In this paper I develop a model of a competitive financial system with unrestricted but costly entry and an endogenously determined number of competing financial institutions (“banks” for short). Banks can make standard loans on which plentiful historical data are available and unanimous agreement exists on default probabilities. Or banks can innovate and make new loans on which limited historical data are available, leading to possible disagreement over default probabilities. In equilibrium, banks make zero profits on standard loans and positive profits on innovative loans, which engenders innovation incentives for banks. But innovation brings with it the risk that investors could disagree with the bank that the loan is worthy of continued funding and hence could withdraw funding at an interim stage, precipitating a financial crisis. The degree of innovation in the financial system is determined by this trade-off. Welfare implications of financial innovation and mechanisms to reduce the probability of crises are discussed.

This paper focuses on stocks that experience major price changes. Using analyst reports as a proxy, I find that price events accompanied by information are followed by drift, while no-information ones result in reversals. One interpretation of these results is that investors underreact to news about fundamentals and overreact to other shocks that move stock prices. Consistent with this hypothesis, information-based price changes are more strongly correlated with future earnings surprises than no-information ones. Furthermore, drift exists only when the direction of the price move and of the change in analyst recommendations have the same sign. Finally, the ratio of no-information to information-based price shocks is strongly correlated with aggregate implied volatility and also forecasts momentum returns.

I examine how transparency and interdealer trading affects prices investors pay in municipal bond offerings. Real-time trade reporting for municipal bonds started January 31, 2005. The dispersion of purchase prices fell sharply at that time. There was little impact on average markups for most trades, but they increased for purchases of more than $100,000. Bonds often pass through a series of dealers before being placed with a buy-and-hold investor. As the interdealer trades progress, trade sizes decline and trade prices rise. Markups on investor purchases increase with the amount of interdealer trading before the trade.