Knowledge that Transforms

Using a normalized CES function with factor-augmenting technical progress, we estimate a supply-side system of the U.S. economy from 1953 to 1998. Avoiding potential estimation biases that may have occurred in earlier studies and putting a high emphasis on data consistency, we obtain robust results not only for the aggregate elasticity of substitution but also for the parameters of labor and capital augmenting technical change. We find that the elasticity of substitution is significantly below unity and that technical progress shows an asymmetrical pattern where the growth of labor-augmenting technical progress is exponential, while that of capital is hyperbolic or logarithmic.

This paper shows that the United Kingdom since 1975 has exhibited a pattern of job polarization with rises in employment shares in the highest- and lowest-wage occupations. This is not entirely consistent with the idea of skill-biased technical change as a hypothesis about the impact of technology on the labor market. We argue that the “routinization” hypothesis recently proposed by Autor, Levy, and Murnane (2003) is a better explanation of job polarization, though other factors may also be important. We show that job polarization can explain one-third of the rise in the log(50/10) wage differential and one-half of the rise in the log(90/50).

In this paper, we describe the results of a study assessing the relationship between the certification of teachers by the National Board for Professional Teaching Standards (NBPTS) and elementary-level student achievement. We examine whether NBPTS assesses the most effective applicants, whether certification by NBPTS serves as a signal of teacher quality, and whether completing the NBPTS assessment process serves as a catalyst for increasing teacher effectiveness. We find consistent evidence that NBPTS is identifying the more effective teacher applicants and that National Board Certified Teachers are generally more effective than teachers who never applied to the program. The statistical significance and magnitude of the “NBPTS effect,” however, differs significantly by grade level and student type. We do not find evidence that the NBPTS certification process itself does anything to increase teacher effectiveness.

This paper uses Consumer Expenditure Survey data and a seminonparametric statistical model to estimate life-cycle profiles of consumption, controlling for demographics, cohort, and time effects. We construct age profiles for total and nondurable consumption as well as expenditure patterns for consumer durables. Special emphasis is placed on the comparison of different approaches to control for changes in demographics over the life cycle. We find significant humps over the life cycle for total, nondurable, and durable expenditures. Changes in household

This paper presents theory and evidence on the relationship between inequality and institutional quality. We exhibit a model in which the two may dynamically reinforce each other and set to test this relationship with a broad array of institutional measures. The double causality between institutional strength and a more equal distribution of income is empirically established using dynamic panel and linear feedback analysis.

This paper evaluates the effects of patent protection on pharmaceutical innovations for 26 countries that established pharmaceutical patent laws during 1978–2002. Controlling for country characteristics through matched sampling techniques to establish two proper comparison sets among 92 sampled countries and through country-pair fixed-effects regressions, this study yields robust results. National patent protection alone does not stimulate domestic innovation, as estimated by changes in citation-weighted U.S. patent awards, domestic R&D, and pharmaceutical industry exports. However, domestic innovation accelerates in countries with higher levels of economic development, educational attainment, and economic freedom. Additionally, there appears to be an optimal level of intellectual property rights regulation above which further enhancement reduces innovative activities.

Beginning in the late 1980s, American corporations began increasingly linking the compensation of central research personnel to the economic objectives of the corporation. This paper examines the impact of the shifting compensation of the heads of corporate research and development. Among firms with centralized R&D organizations, a clear relationship emerges: more long-term incentives (such as stock options and restricted stock) are associated with more heavily cited patents. These incentives also appear to be associated with more patent awards and patents of greater originality. Short-term incentives appear to be unrelated to measures of innovation.

Are there productivity spillovers from FDI to domestic firms, and, if so, how much should host countries be willing to pay to attract FDI? To examine these questions, we use a plant-level panel covering U.K. manufacturing from 1973 through 1992. Consistent with spillovers, we estimate a robust and significantly positive correlation between a domestic plant's TFP and the foreign-affiliate share of activity in that plant's industry. Typical estimates suggest that a 10-percentage-point increase in foreign presence in a U.K. industry raises the TFP of that industry's domestic plants by about 0.5%. We also use these estimates to calculate the per-job value of these spillovers at about £2,400 in 2000 prices ($4,300). These calculated values appear to be less than per-job incentives governments have granted in recent high-profile cases, in some cases several times less.

We examine inference in panel data when the number of groups is small, as is typically the case for difference-in-differences estimation and when some variables are fixed within groups. In this case, standard asymptotics based on the number of groups going to infinity provide a poor approximation to the finite sample distribution. We show that in some cases the t-statistic is distributed as t and propose simple two-step estimators for these cases. We apply our analysis to two well-known papers. We confirm our theoretical analysis with Monte Carlo simulations.

A growing literature documents important gains in asset return volatility forecasting via use of realized variation measures constructed from high-frequency returns. We progress by using newly developed bipower variation measures and corresponding nonparametric tests for jumps. Our empirical analyses of exchange rates, equity index returns, and bond yields suggest that the volatility jump component is both highly important and distinctly less persistent than the continuous component, and that separating the rough jump moves from the smooth continuous moves results in significant out-of-sample volatility forecast improvements. Moreover, many of the significant jumps are associated with specific macroeconomic news announcements.