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991.
This Article is based on a presentation given at Seton Hall University School of Law's Seventh Annual Health Law Symposium on February 12, 1999.  相似文献   
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This paper examines the linkage between crack market activity and gunhomicide suggested by Blumstein (1995), who argues that the arrival ofcrack stimulated an increased availability of guns among juveniles. Thisgreater availability of guns, the argument continues, is responsible for thesharp upswing in juvenile homicide experienced in the United States in themid-1980s. Using city-level data on crack arrests and gun-related juvenilehomicide, we fit a change-point version of the Bass (1969) model ofinnovation diffusion. We find that, in most large American cities, thediffusion process for crack cocaine experienced an onset of dramatic growththat was followed by a similar, slightly slower growth in gun homicidescommitted by juveniles. We further use cluster analysis to find that thespatial patterning of the two processes is similar, starting on the East andWest Coasts and working their way toward other regions of the nation. Gunuse in homicide among slightly older offenders (ages 18–24) alsoexperienced a change at roughly the same time as the juveniles, but the rateof diffusion was considerably milder than for the younger group; offendersages 25 or older generally show no growth in gun-related homicide whatsoever. In addition, there is no detectable surge in juvenile nongun homicide activity. Based on these findings, we conclude that the crack cocaine markets–gun availability linkage is highly plausible, and we suggest directions for future research in clarifying the dynamics of the late-1980s surge in juvenile homicide.  相似文献   
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Montgomery  Michael R.  Bean  Richard 《Public Choice》1999,99(3-4):403-437
Two opposing models of public-goods undersupply are those of “market failure” and “government failure”. Empirical work on the relative explanatory power of these two frameworks has been limited by the scarcity of acceptable data. The case of climate-controlled walkways in major urban cores is a rare instance where such difficulties can be overcome. We investigate the supply of CCWs in 55 large city-cores in North America. We find that (1) CCW networks are well-supplied by market forces, when (2) such forces are not frustrated by government policy. We also find evidence that (3) rules-based regimes dominate discretion-based regimes. These results are consistent with the position that the “government-failure” paradigm is a viable alternative to the traditional “market failure” paradigm.  相似文献   
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"This article compares two sources of data on Mexico-U.S. migration, based on radically different methodologies: the Mexican Migration Project (Promig) and the National Survey of Population Dynamics (Enadid).... This comparative study shows that a micro-social design drawing on multiple community samples, such as Promig, can solve the methodological conflict between specificity and representativeness.... The authors' research also highlights the problem of selectivity and specificity entailed by traditional surveys such as Enadid as a result of restricting their samples to international residents in Mexico and attempting to explain such a complex, socioeconomic process using a limited number of variables." (EXCERPT)  相似文献   
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Sutter  Daniel 《Public Choice》1999,98(1-2):29-41
Stable, enforceable property rights over resources normally furthers economic efficiency. I argue that stable rights to government created rents and wealth transfers, by contrast, generate inefficiency. Secure rights to receive transfers increases rent-seekers' incentive to make political investments creating new transfers. I demonstrate the point using a two period rent-seeking game. Contestable transfers reduce the probability of establishing a transfer program and aggregate rent-seeking expenditures. Strengthening transfer recipients' rights increases the difficulty of eliminating a transfer program.  相似文献   
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Health care reform became a premier issue on the U.S. policy agenda in the 1990s. While the comprehensive proposal put forth by President Clinton failed, states and the federal government successfully pursued a variety of lesser initiatives. This article focuses on a set of reforms intended to make private health insurance more accessible and affordable to individuals and workers in small firms. It outlines the key arguments made by experts to justify stronger regulation of health insurance and the options and difficult tradeoffs that must be considered in policy design. It then examines the scope and strength of legislation adopted by 45 states and the federal government from 1990 to 1996. The substantial variation in state policies demonstrates that even though insurance market reform was the one issue that commanded nearly universal support in the health care debate, few design features were universally accepted by those who crafted the reforms. The article concludes by assessing the pattern of state and federal action. The reforms represent some progress on nominal access to insurance but little progress on the affordability of insurance for individuals and small groups. Few of the reforms present a serious challenge to existing practices and interests of the insurance industry. This pattern of policy design reflects the logical and political constraints of incrementalism. In a system where insurance coverage is voluntary, changes to increase access for one group tend to increase costs and thereby decrease access for another segment of the population. In addition, because incremental reforms will not attract sustained attention and support from the general public, it is politically difficult to impose substantial new regulation on a powerful industry.  相似文献   
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