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161.
Cocaine in Wayne County Medical Examiner's cases   总被引:1,自引:0,他引:1  
We determined the incidence of detection of cocaine or its metabolites in Wayne County (Michigan) Medical Examiner's cases from 1984 to 1987. Over this four-year period there was a significant (P less than 0.01) increase each year in evidence of recent cocaine use in this population, reaching 38.3% of all tested cases in 1987. Much of this increase was accounted for by homicide victims, especially those in their third or fourth decade of life, of whom 58.6 and 56.3%, respectively, tested positive in 1987. There was a large increase in recent cocaine use in teenage homicide victims in 1987, having previously changed little from 1984 to 1986. In victims of drug abuse, recent cocaine use also increased significantly (p less than 0.01) each year, reaching 47.6% in 1987, generally in combination with heroin. Although deaths attributed solely to cocaine were not as common, they also increased significantly each year from 4 in 1984 to 25 in 1987. Compared with the general population, those who use cocaine in Wayne County are more likely than those who do not to die prematurely, often as a result of violence.  相似文献   
162.
We develop an approach to conducting large-scale randomized public policy experiments intended to be more robust to the political interventions that have ruined some or all parts of many similar previous efforts. Our proposed design is insulated from selection bias in some circumstances even if we lose observations; our inferences can still be unbiased even if politics disrupts any two of the three steps in our analytical procedures; and other empirical checks are available to validate the overall design. We illustrate with a design and empirical validation of an evaluation of the Mexican Seguro Popular de Salud (Universal Health Insurance)program we are conducting. Seguro Popular, which is intended to grow to provide medical care, drugs, preventative services, and financial health protection to the 50 million Mexicans without health insurance, is one of the largest health reforms of any country in the last two decades. The evaluation is also large scale, constituting one of the largest policy experiments to date and what may be the largest randomized health policy experiment ever.  相似文献   
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A blind study to determine whether virtual toolmarks created using a computer could be used to identify and characterize angle of incidence of physical toolmarks was conducted. Six sequentially manufactured screwdriver tips and one random screwdriver were used to create toolmarks at various angles. An apparatus controlled tool angle. Resultant toolmarks were randomly coded and sent to the researchers, who scanned both tips and toolmarks using an optical profilometer to obtain 3D topography data. Developed software was used to create virtual marks based on the tool topography data. Virtual marks generated at angles from 30 to 85° (5° increments) were compared to physical toolmarks using a statistical algorithm. Twenty of twenty toolmarks were correctly identified by the algorithm. On average, the algorithm misidentified the correct angle of incidence by ?6.12°. This study presents the results, their significance, and offers reasons for the average angular misidentification.  相似文献   
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Few political institutions are as central to theories of lawmaking as the executive veto. Despite its importance, institutional continuity at the national level has precluded identification of empirical effects of the veto on legislative behavior. We address this limitation and present evidence from the states demonstrating how the veto affects the formation of legislative coalitions and, indirectly, executive influence over policymaking. We find consistent evidence that the presence and strength of gubernatorial veto powers affect the lawmaking behavior of state legislatures. Our analysis shows how institutional provisions condition executives' ability to affect policy outcomes in separation‐of‐powers systems.  相似文献   
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