Knowledge that Transforms

This paper examines the relation between expected stock returns and their conditional volatility over different holding periods and across different states of the economy. Seminonparametric density estimation and Monte Carlo integration are used to obtain the expected returns and conditional volatility at various holding intervals. We uncover a significantly positive risk and return relation at long holding intervals, such as one and two years, which is nonexistent at short holding periods such as one month. We also show that the existing finding in the literature of a negative risk and return relation may be attributable to misspecification.

This paper bridges the gap between processes where shocks are permanent and those with transitory shocks by formulating a process in which the long-run impact of each innovation is time-varying and stochastic. In the stochastic permanent breaks (STOPBREAK) process, frequent transitory shocks are supplemented by occasional permanent shifts. Consistency and asymptotic normality of quasi-maximum-likelihood estimates is established, and locally best hypothesis tests of the null of a random walk are developed. The model is applied to relative prices of pairs of stocks and significant test statistics result.

This is the first study that decomposes unemployment into its structural and cyclical components and investigates their impact on income distribution, controlling for the influence of inflation. Increases in structural unemployment have a substantial aggravating impact on income inequality. Inflation has a progressive impact, which is due to the unexpected component. The study demonstrates that previous work failed to take into account the stochastic trend behavior of the variables. Consequently, specifications used by previous research cannot predict the behavior of income shares after 1983, whereas the specification used by this paper generates accurate forecasts. The results also indicate that a sustained GNP growth is not necessarily associated with an improvement in income inequality, because sustained GNP growth can coexist with increased structural unemployment.

An important factor driving energy policy over the past two decades has been the “energy paradox,” the perception that consumers apply unreasonably high hurdle rates to energy-saving investments. We explore one possible explanation for this apparent puzzle: that realized returns fall short of the returns promised by engineers and product manufacturers. Using a unique data set, we find that the realized return to attic insulation is statistically significant, but the median estimate (9.7%) is almost identical to a discount rate for this investment implied by a CAPM analysis. We conclude that the case for the energy paradox is weaker than has previously been believed.

In this paper, we analyze the decision by teachers to leave the profession in a dependent competing risks framework. The econometric model allows for a flexible, semiparametric specification of the duration-dependence structure and of the unobserved heterogeneity distribution in each exit-specific hazard function. Our results obtained for a large sample of UK teachers affirm the importance of teacher salaries and opportunity wages in the turnover decision of teachers and illustrate the insight gained from differentiating between multiple destinations or exit types.

This paper studies the optimal consumption behavior of individuals who face borrowing limitations that vary stochastically with their income. This framework is motivated by new empirical evidence that I document in U.S. aggregate data: predictable growth in consumer credit is significantly related to consumption growth, a finding that is inconsistent with existing models of consumer behavior. The time-varying liquidity constraint model considered here correctly predicts two key properties of the U.S. aggregate data: the correlation of consumption growth with predictable credit growth documented in this paper, and the well-known correlation between consumption growth and predictable income growth that has been documented extensively elsewhere.

In the existing literature, conditional forecasts in the vector autoregressive (VAR) framework have not been commonly presented with probability distributions. This paper develops Bayesian methods for computing the exact finite-sample distribution of conditional forecasts. It broadens the class of conditional forecasts to which the methods can be applied. The methods work for both structural and reduced-form VAR models and, in contrast to common practices, account for parameter uncertainty in finite samples. Empirical examples under both a flat prior and a reference prior are provided to show the use of these methods.

Acommon model for security price dynamics is the continuous-time stochastic volatility model. For this model, Hull and White (1987) show that the price of a derivative claim is the conditional expectation of the Black-Scholes price with the forward integrated variance replacing the Black-Scholes variance. Implementing the Hull and White characterization requires both estimates of the price dynamics and the conditional distribution of the forward integrated variance given observed variables. Using daily data on close-to-close price movement and the daily range, we find that standard models do not fit the data very well and that a more general three-factor model does better, as it mimics the long-memory feature of financial volatility. We develop techniques for estimating the conditional distribution of the forward integrated variance given observed variables.

In this study, we use data for 1981 through 1994 on a large sample of U.S. companies to examine the persistence of incremental industry, corporate-parent, and business-specific effects on profitability. Our results indicate that the incremental effects of industry on profitability persist longer than the incremental effects of the corporate parent and of the specific business. Changes in industry structure have a more persistent impact on profitability than do changes in firm structure.

Research on the distribution of income during the 1980s has identified a trend towards increasing inequality, which may be the continuation and acceleration of trends spanning several decades. This paper explores to what extent behavioral responses to the tax changes during the 1980s may also explain the rising inequality. The 1986 Tax Reform Act is used as a natural experiment to explore the roles played by both taxes and a variety of nontax factors. Our principal finding is that both tax rates and nontax factors appear to have had significant effects on relative income growth during the late 1980s.