The Divergence of Human Capital Levels Across Cities

Over the past 30 years, the share of adult populations with college degrees increased more in cities with higher initial schooling levels than in initially less educated places. This tendency appears to be driven by shifts in labor demand as there is an increasing wage premium for skilled people working in skilled cities. In this paper, we present a model where the clustering of skilled people in metropolitan areas is driven by the tendency of skilled entrepreneurs to innovate in ways that employ other skilled people and by the elasticity of housing supply.

How Hot Is Radiation?

A self-consistent approach to nonequilibrium radiation temperature is introduced using the distribution of the energy over states. We begin rigorously with ensembles of Hilbert spaces and end with practical examples based mainly on the far from equilibrium radiation of lasers. We show that very high, but not infinite, laser radiation temperatures depend on intensity and frequency. Heuristic "temperatures" derived from a misapplication of equilibrium arguments are shown to be incorrect. More general conditions for the validity of nonequilibrium temperatures are also established.Comment: 26 pages, revised, LaTeX, 3 encapsulated PostScript figure

Congressional committee membership is less important thanpreviously thought, but chairs are really influential

Political scientists and commentators have generally believed that Congressional committees wield a great deal of power over how federal spending is distributed. But new research from Christopher R. Berry and Anthony Fowler suggests that committee positions actually hold relatively little influence. Committee chairs, on the other hand, are far more important than had been previously thought

Leadership or luck? Randomization inference for leader effects in politics, business, and sports

Anecdotal evidence suggests that some leaders are more effective than others but observed differences in outcomes between leaders could be attributable to chance variation. To solve this inferential problem, we develop a quantitative test of leader effects that provides more reliable inferences than previous strategies, and we implement the test in the settings of politics, business, and sports. We find significant effects of political leaders, particularly in nondemocracies. We find little evidence that chief executive officers influence the performance of their firms. In addition, we find clear evidence that sports coaches matter for a wide range of outcomes in football, basketball, baseball, and hockey

Voters, Non-voters, and the Implications of Election Timing for Public Policy

This paper makes use of variation in the timing of local elections to shed light on one of the core questions in democratic politics: what would happen if everyone voted? Does a low voter turnout rate imply that a small subset of special interest voters controls politics and policy? Or, are voters largely representative of non-voters such that neither the outcomes of elections nor resulting public policies would change even if everyone participated? Rather than rely on surveys of nonvoters to extrapolate their hypothetical behavior, we rely on a natural experiment created by a 1980s change in the California Election Code, which allowed school districts to change their elections from off-cycle to on-cycle. Because we are able to observe very large within-district changes in voter turnout resulting from changes in election timing, we are able to isolate the effect of turnout on policy outcomes, including teacher salaries and student achievement tests. Our analysis demonstrates that changes in voter turnout do affect public policy, but modestly

Voters, Non-voters, and the Implications of Election Timing for Public Policy

This paper makes use of variation in the timing of local elections to shed light on one of the core questions in democratic politics: what would happen if everyone voted? Does a low voter turnout rate imply that a small subset of special interest voters controls politics and policy? Or, are voters largely representative of non-voters such that neither the outcomes of elections nor resulting public policies would change even if everyone participated? Rather than rely on surveys of nonvoters to extrapolate their hypothetical behavior, we rely on a natural experiment created by a 1980s change in the California Election Code, which allowed school districts to change their elections from off-cycle to on-cycle. Because we are able to observe very large within-district changes in voter turnout resulting from changes in election timing, we are able to isolate the effect of turnout on policy outcomes, including teacher salaries and student achievement tests. Our analysis demonstrates that changes in voter turnout do affect public policy, but modestly

Gravitational wave energy spectrum of a parabolic encounter

We derive an analytic expression for the energy spectrum of gravitational waves from a parabolic Keplerian binary by taking the limit of the Peters and Matthews spectrum for eccentric orbits. This demonstrates that the location of the peak of the energy spectrum depends primarily on the orbital periapse rather than the eccentricity. We compare this weak-field result to strong-field calculations and find it is reasonably accurate (~10%) provided that the azimuthal and radial orbital frequencies do not differ by more than ~10%. For equatorial orbits in the Kerr spacetime, this corresponds to periapse radii of rp > 20M. These results can be used to model radiation bursts from compact objects on highly eccentric orbits about massive black holes in the local Universe, which could be detected by LISA.Comment: 5 pages, 3 figures. Minor changes to match published version; figure 1 corrected; references adde

Fiscal Consequences of Electoral Institutions

There are more than 500,000 elected officials in the United States, 96 percent of whom serve in local governments. Electoral density - the number of elected officials per capita or per governmental unit - varies greatly from place to place. The most electorally dense county has more than 20 times the average number of elected officials per capita. In this paper, we offer the first systematic investigation of the link between electoral density and fiscal policy. Drawing on principal-agent theories of representation, we argue that electoral density presents a tradeoff between accountability and monitoring costs. Increasing the number of specialized elected offices promotes issue unbundling, reducing slack between citizen preferences and government policy; but the costs of monitoring a larger number of officials may offset these benefits, producing greater latitude for politicians to pursue their own goals at the expense of citizen interests. Thus, we predict diminishing returns to electoral density, suggesting a U-shaped relationship between the number of local officials and government fidelity to citizen preferences. Using a county-level dataset of all elected officials in the United States, we evaluate this theory along with competing theories from the existing literature. Empirically, we find evidence that public sector size decreases with electoral density up to a point, beyond which budgets grow as more officials are added within a community