26,368 research outputs found

    Winning Lessons from the NAFTA Loss

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    [Excerpt] The period around last fall\u27s Congressional vote on the North American Free Trade Agreement (NAFTA) was the best of times and the worst of times for organized labor. The threat of NAFTA\u27s passage galvanized tens of thousands of rank-and-file union activists. Working in local coalitions with farmers, environmentalists, consumer advocates, Perot supporters, and other forces, union members waged a spirited, high-profile campaign over a public-policy question affecting millions of Americans

    Comparisons of two quantile regression smoothers

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    The paper compares the small-sample properties of two non-parametric quantile regression estimators. The first is based on constrained B-spline smoothing (COBS) and the other is based on a variation and slight extension of a running interval smoother, which apparently has not been studied via simulations. The motivation for this paper stems from the Well Elderly 2 study, a portion of which was aimed at understanding the association between the cortisol awakening response and two measures of stress. COBS indicated what appeared be an usual form of curvature. The modified running interval smoother gave a strikingly different estimate, which raised the issue of how it compares to COBS in terms of mean squared error and bias as well as its ability to avoid a spurious indication of curvature. R functions for applying the methods were used in conjunction with default settings for the various optional arguments. The results indicate that the modified running interval smoother has practical value. Manipulation of the optional arguments might impact the relative merits of the two methods, but the extent to which this is the case remains unknown.Comment: 18 pp, 5 figure

    ANCOVA: A global test based on a robust measure of location or quantiles when there is curvature

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    For two independent groups, let Mj(x)M_j(x) be some conditional measure of location for the jjth group associated with some random variable YY, given that some covariate X=xX=x. When Mj(x)M_j(x) is a robust measure of location, or even some conditional quantile of YY, given XX, methods have been proposed and studied that are aimed at testing H0H_0: M1(x)=M2(x)M_1(x)=M_2(x) that deal with curvature in a flexible manner. In addition, methods have been studied where the goal is to control the probability of one or more Type I errors when testing H0H_0 for each x∈{x1,…,xp}x \in \{x_1, \ldots, x_p\}. This paper suggests a method for testing the global hypothesis H0H_0: M1(x)=M2(x)M_1(x)=M_2(x) for ∀x∈{x1,…,xp}\forall x \in \{x_1, \ldots, x_p\} when using a robust or quantile location estimator. An obvious advantage of testing pp hypotheses, rather than the global hypothesis, is that it can provide information about where regression lines differ and by how much. But the paper summarizes three general reasons to suspect that testing the global hypothesis can have more power. 2 Data from the Well Elderly 2 study illustrate that testing the global hypothesis can make a practical difference.Comment: 23 pp 2 Figure

    Average Interpolation Under the Maximum Angle Condition

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    Interpolation error estimates needed in common finite element applications using simplicial meshes typically impose restrictions on the both the smoothness of the interpolated functions and the shape of the simplices. While the simplest theory can be generalized to admit less smooth functions (e.g., functions in H^1(\Omega) rather than H^2(\Omega)) and more general shapes (e.g., the maximum angle condition rather than the minimum angle condition), existing theory does not allow these extensions to be performed simultaneously. By localizing over a well-shaped auxiliary spatial partition, error estimates are established under minimal function smoothness and mesh regularity. This construction is especially important in two cases: L^p(\Omega) estimates for data in W^{1,p}(\Omega) hold for meshes without any restrictions on simplex shape, and W^{1,p}(\Omega) estimates for data in W^{2,p}(\Omega) hold under a generalization of the maximum angle condition which previously required p>2 for standard Lagrange interpolation

    Gun Deaths Outpace Motor Vehicle Deaths in 17 States and the District of Columbia in 2013

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    In this report we find that Seventeen states and the District of Columbia already experience gun death rates that exceed their motor vehicle-related death rates. If current trends continue, the number of states where gun deaths outpace motor vehicles deaths will only continue to increase. The historic drop in motor vehicle deaths illustrates how health and safety regulation can reduce deaths and injuries that were at one time thought to be unavoidable. Such an approach to injury prevention has been applied to every product Americans come into contact with every day except for one: guns. And as is the case with motor vehicles, health and safety regulation could reduce deaths and injuries associated with firearms.Comprehensive regulation of the firearms industry and its products could include: minimum safety standards (i.e., specific design standards and the requirement of safety devices); bans on certain types of firearms such as "junk guns" and military-style assault weapons; limits on firepower; restrictions on gun possession by those convicted of a violent misdemeanor; expanded prohibitions on possession by persons with a history of domestic violence and better enforcement of existing prohibitions; heightened restrictions on the carrying of loaded guns in public; more detailed and timely data collection on gun production, sales, use in crime, as well as involvement in injury and death; and, public education about the extreme risks associated with exposure to firearms.America is reaping the benefits of decades of successful injury prevention strategies on its highways, but continues to pay an unacceptable, yet equally preventable, cost in lives lost every year to gun violence

    Thin film strain transducer

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    A strain transducer system and process for making the same is disclosed. A beryllium copper ring having four strain gages is electrically connected in Wheatstone bridge fashion to the output instrumentation. Tabs are bonded to a balloon or like surface with strain on the surface causing bending of a ring which provides an electrical signal through the gages proportional to the surface strain. A photographic pattern of a one half ring segment as placed on a sheet of beryllium copper for chem-mill etch formation is illustrated
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