3,070 research outputs found

    Minimum Wages and Teen Employment: A Spatial Panel Approach

    Get PDF
    The authors employ spatial econometrics techniques and Annual Averages data from the U.S. Bureau of Labor Statistics for 1990-2004 to examine how changes in the minimum wage affect teen employment. Spatial econometrics techniques account for the fact that employment is correlated across states. Such correlation may exist if a change in the minimum wage in a state affects employment not only in its own state but also in other, neighboring states. The authors show that state minimum wages negatively affect teen employment to a larger degree than is found in studies that do not account for this correlation. Their results show a combined direct and indirect effect of minimum wages on teen employment to be -2.1% for a 10% increase in the real effective minimum wage. Ignoring spatial correlation underestimates the magnitude of the effect of minimum wages on teen employment.minimum wage, teen employment, spatial econometrics

    Spatial Econometric Issues for Bio-Economic and Land-Use Modeling

    Get PDF
    We survey the literature on spatial bio-economic and land-use modelling and review thematic developments. Unobserved site-specific heterogeneity is common in almost all of the surveyed works. Heterogeneity appears also to be a significant catalyst engendering significant methodological innovation. To better equip prototypes to adequately incorporate heterogeneity, we consider a smorgasbord of extensions. We highlight some problems arising with their application; provide Bayesian solutions to some; and conjecture solutions for others.spatial econometrics, bio-economic and land-use modelling, Bayesian solution, Land Economics/Use,

    Institutional Design and Policy Responsiveness in US States

    Get PDF
    There is significant disagreement on the moderating role of institutions on policy responsive- ness, yet overwhelmingly research in state politics has focused on single institutions. This project leverages a new aggregate scale of state institutions to evaluate if the collective insti- tutional context moderates the influence of public opinion on policy. I use a recently released latent scale of institutional context and find that high levels of accountability pressure strongly strengthen public opinion’s influence on policy for both economic and social policy, while the strength of a state’s checks and balance system is largely unrelated to policy responsiveness. These results demonstrate the importance of incorporating aggregate institutional design into our understanding of the role of institutions in state politics, and that collectively institutions play a large role in determining how public opinion is translated into policy

    Phase Stability and Segregation in Alloy 22 Base Metal and Weldments

    Full text link
    The current design of the waste disposal containers relies heavily on encasement in a multi-layered container, featuring a corrosion barrier of Alloy 22, a Ni-Cr-Mo-W based alloy with excellent corrosion resistance over a wide range of conditions. The fundamental concern from the perspective of the Yucca Mountain Project, however, is the inherent uncertainty in the (very) long-term stability of the base metal and welds. Should the properties of the selected materials change over the long service life of the waste packages, it is conceivable that the desired performance characteristics (such as corrosion reistance) will become compromised, leading to premature failure of the system. To address this, we will study the phase stability and solute segregation characteristics of Alloy 22 base metal and welds. A better understanding of the underlying microstructural evolution tendencies, and their connections with corrosion behavior will (in turn) produce a higher confidence in the extrapolated behavior of the container materials over time periods that are not feasibly tested in a laboratory. Additionally, the knowledge gained here may potentially lead to cost savings through development of safe and realistic design constraints and model assumptions throughout the entire disposal system

    Parametrization of Realistic Bethe-Salpeter Amplitude for the Deuteron

    Get PDF
    The parametrization of the realistic Bethe-Salpeter amplitude for the deuteron is given. Eight components of the amplitude in the Euclidean space are presented as an analytical fit to the numerical solution of the Bethe-Salpeter equation in the ladder approximation. An applicability of the parametrization to the observables of the deuteron is briefly discussed.Comment: LaTeX, 11 pages, 2 Postscript figures; Text of the Fortran program is available from the author by reques

    Solar wind turbulent spectrum from MHD to electron scales

    Full text link
    Turbulent spectra of magnetic fluctuations in the free solar wind are studied from MHD to electron scales using Cluster observations. We discuss the problem of the instrumental noise and its influence on the measurements at the electron scales. We confirm the presence of a curvature of the spectrum ∌exp⁥kρe\sim \exp{\sqrt{k\rho_e}} over the broad frequency range ∌[10,100]\sim[10,100] Hz, indicating the presence of a dissipation. Analysis of seven spectra under different plasma conditions show clearly the presence of a quasi-universal power-law spectrum at MHD and ion scales. However, the transition from the inertial range ∌k−1.7\sim k^{-1.7} to the spectrum at ion scales ∌k−2.7\sim k^{-2.7} is not universal. Finally, we discuss the role of different kinetic plasma scales on the spectral shape, considering normalized dimensionless spectra.Comment: to be published in "Solar Wind 12 Proceedings", AIP Conference Proceedings, 201

    Local and global spatial effects in hierarchical models

    Get PDF
    Hierarchical models have a long history in empirical applications; recognition of the fact that many datasets of interest to applied econometricians are nested; counties within states, pupils within school, regions within countries, etc. Just as many datasets are characterized by nesting, many are also characterized by the presence of spatial dependence or spatial heterogeneity. Significant advances have been made in developing econometric techniques and models to allow applied econometricians to address this spatial dimension to their data. This paper fuses these two literatures together and combines a hierarchical model with the two general spatial econometric models

    Agro-environmental evaluation of vineyard management using organic farming and integrated plant production systems

    Get PDF
    Organic farming is often considered to be the most environmentally-friendly crop management system, even if integrated production also aims at decreasing the impact of agriculture on the natural environment. In order to establish references for the agro-environmental evaluation of these two production systems in relation to grape growing, INRA carried out an initial study from 2001 to 2004 at the plot scale. This study focused on two grape varieties (Merlot N and Cabernet Sauvignon) in its Couhins vineyard (Graves cru classé), located on two organically-farmed plots and two plots using integrated production, a system based on the implementation of decision rules aimed at limiting the number of pest control treatments. Production means only differed in terms of pest control management (choice of products and application strategy). Each of the parcels covered approximately 0.30 ha. An agro-environmental evaluation of these two systems was made for 2003, using the INDIGO Vigne method at the plot level. Because of their nature, the choice of parameters for the indicators used determines the interpretation of the results. Nevertheless, it appears that the environmental impact of integrated production is more favourable in this case than that of organic farming, particularly in terms of pest control and energy indicators. One of the reasons for this is the high number of applications of pest control treatments in organic farming and, as a result, higher energy consumption, as well as the use of copper that has a major impact on deep waters, the ground and the air. The two systems can decrease their environmental impact by limiting the number of tractor runs for soil maintenance. Flexibility appears to be greater in the case of integrated production since, contrary to organic farming, it can use herbicides under the row. The calculation of the agro-environmental evaluation on the parcel using integrated protection with chemical weeding under the row leads to a clear improvement of the energy indicator, without significantly decreasing the value of the pest control indicator. Natural sodding of the inter-row, when the vigour of the vineyard allows it, provides an effective solution since the decrease in the number of tractor runs leads to an improvement of erosion and organic matter indicators. This type of evaluation should be carried out at the scale of a group of plots or of an entire wine-farm. Ground maintenance is an important factor in decreasing the impact of grape growing on the environment. In this respect, organic farming offers some promising prospects

    Do Courts Change Politics? Heller and the Limits of Policy Feedback Effects

    Get PDF
    District of Columbia v. Heller was a landmark ruling in which the Supreme Court established that citizens have a constitutional right to possess firearms in their homes for self-protection. The 5-4 decision—along with the Court’s subsequent ruling in McDonald v. Chicago—upended the prevailing wisdom that the Second Amendment protected the right of the states to assemble militias for collective security. In this Article, we examine the effects of these rulings on gun regulation in the United States and, more to the point, on gun politics. We situate our analysis within several related theoretical frameworks, most notably those focused on policy feedback and on the role of courts in producing social change. We argue that the effects of Heller (together with the parallel decision in McDonald) have been rather limited. We examine the rulings’ first-order effects on pre-existing gun control laws, as well as second-order effects on a number of related outcomes. We find that Heller and its progeny have had generally small or non-existent impacts on gun policy, on the organizational capacities and political strategies of pro-gun and pro-regulation groups, and on public attitudes toward gun regulation. Our findings support a constrained view of the Court’s ability to drive social and political change. We conclude, however, by noting that recent developments—particularly hints that some Supreme Court Justices are eager to develop Second Amendment jurisprudence—have the potential to alter these conclusions

    A Note on Partitioning Effects Estimates Over Space

    Get PDF
    In this paper we provide an applied example for calculating the so-called effects estimates of LeSage and Pace (2009) for partitions of the impacts over space. While the partitioning of the impacts by orders of neighbors over space for the spatial autoregressive (SAR) model is a relatively straightforward procedure, care must be taken in the case of the spatial Durbin model (SDM). We provide an illustration of these calculations for both models using a widely available data set on voter turnout for the 1980 United States presidential election
    • 

    corecore