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31.
In a general model of indivisible good allocation, S?nmez (1999) established that, whenever the core is nonempty for each preference profile, if an allocation rule is strategy-proof, individually rational and Pareto optimal, then the rule is a selection from the core correspondence, and the core correspondence must be essentially single-valued. This paper studies the converse claim of this result. I demonstrate that whenever the preference domain satisfies a certain condition of `richness', if the core correspondence is essentially single-valued, then any selection from the core correspondence is strategy-proof (even weakly coalition strategy-proof, in fact). In particular, on the domain of preferences in which each individual has strict preferences over his own assignments and there is no consumption externality, such an allocation rule is coalition strategy-proof. And on this domain, coalition strategy-proofness is equivalent to Maskin monotonicity, an important property in implementation theory. Received: 22 February 2000/Accepted: 22 January 2002 I am grateful to Ryo-ichi Nagahisa, Shinji Ohseto, Hiroshi Ono, Tomoichi Shinotsuka and Shigehiro Serizawa for valuable comments. And I am indebted to two anonymous referees for useful suggestions. Especially, I owe the present proof of Lemma 2 to one referee. I also thank Yukihiko Funaki, Atsushi Kajii, Mamoru Kaneko, Eiichi Miyagawa, Tatsuyoshi Saijo, Manimay Sengupta, Yves Sprumont, Yoshikatsu Tatamitani, Manabu Toda, Takashi Ui, Takehiko Yamato, Naoki Yoshihara and the participants of the seminars in Hokkaido University, Kansai University, ISER (Osaka University), Otaru University of Commerce and Tsukuba University. All errors are my own responsiblity.  相似文献   
32.
1. Most diagnosed cases of tardive dyskinesia (TD) are mildly inconvenient to the patient, but some can be severe or life-threatening. The primary goal of intervention should be early identification of abnormal movements related to TD and the prescribing of an appropriate medication regimen. 2. Unless specific training occurs and a specific monitoring system is in place, TD movements may be missed. However, not all movements are necessarily related to TD. 3. Although screening and monitoring are valuable, nothing is more important than prevention. New medications must be developed that do not carry the risk of TD, and other approaches to treat TD must be developed.  相似文献   
33.
The authors investigated the prevalence of recurrent pain in a college student sample. Of the 1,564 students surveyed, 467 (29%) indicated that they had experienced recurrent pain at an intensity that was mostly in the mild-to-moderate range. Students who reported having recurrent pain were significantly older and more depressed than students who did not indicate they suffered from recurrent pain. Pain intensity was positively correlated (r = .14) with depression among the students who reported having recurrent pain. Implications of the findings for future research, treatment, and health promotion efforts are discussed.  相似文献   
34.
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
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State governments exercise significant powers to regulate the economic and social activities of resident aliens. We review the laws of the six leading states of immigrant settlement regulating access of noncitizens to 23 occupations, updating existing studies from 1946–77. Citizenship requirements for these occupations have plummeted, a change we attribute to federal court decisions, advisory opinions of state attorneys general, and state legislative and administrative action. There are numerous additional citizenship requirements in the statutes of the six states, although these appear to be poorly enforced. The authority of states to regulate their political communities is the most important remaining constitutionally valid basis of citizenship requirements. States define their political community broadly, leading to questionable exclusions of noncitizens from important activities.  相似文献   
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This article explores two problems analysts face in determining how to estimate values for children's health and safety risk reductions. The first addresses the question: Do willingness‐to‐pay estimates for health risk changes differ across children and adults and, if so, how? To answer this question, the article first examines the potential effects of age and risk preferences on willingness to pay. A summary of the literature reporting empirical evidence of differences between willingness to pay for adult health and safety risk reductions and willingness to pay for health and safety risk reductions in children is also provided. The second dimension of the problem is a more fundamental issue: Whose perspective is relevant when valuing children's health effects—society's, children's, adults‐as‐children, or parents'? Each perspective is considered, followed ultimately by the conclusion that adopting a parental perspective through an intrahousehold allocation model seems closest to meeting the needs of the estimation problem at hand. A policy example in which the choice of perspective affects the outcome of a regulatory benefit‐cost analysis rounds out the article and emphasizes the importance of perspective.  相似文献   
39.
Governments around the world combat inequality by means of group-specific redistribution. Some pursue redistribution that benefits groups, but also wish to avoid accentuating or even recognizing group distinctions. This poses a dilemma that they try to resolve by adjusting the category system used to target redistribution. There are three types of adjustment: accommodation (the multicultural approach), denial (the ideal-typical liberal solution), and replacement (a compromise). In replacement the targets of redistributive policies are constructed to avoid accentuation or recognition of inconvenient group distinctions, but still allow redistribution that benefits these groups. Replacement is increasingly in demand around the world because the disadvantages of multiculturalism are becoming apparent while denial is hard to sustain in the face of group inequality. The actual effect of replacement is little researched and less understood, however. Does it resolve the dilemma of recognition? Two examples–India and Nigeria–where replacement has been tried ever since the 1950s cast doubt on its viability.  相似文献   
40.
This study concerned the immunological correlates of stress and work. Self reported stress, emotional state, ego-strength, and defensiveness were examined in relation to measures of cellular immunity (T-cell response to Con A and number of T4 and T8 cells) and humoral immunity (concentrations of immunoglobulins and complement components in plasma) in a group of 96 Norwegian female bank employees. The analyses showed that workload, the stress factor with the highest group mean, was associated with number of T-cells, while strain due to body posture during work was related to concentrations of IgM and C3. Further, depression was significantly correlated with IgM concentration and T-cell number, and anxiety with C3 concentration. T-cell activity was the immunological parameter most consistently associated with psychological well-being, showing positive correlations with defensiveness and ego-strength and negative correlations with anxiety and depression. In conclusion, T-cell number and concentrations of IgM and C3 were sensitive to both work-related stress experience and emotional distress. Coping abilities, indicated by the MMPI Ego-strength scale and emotional distress, were reflected in T-cell activity; insufficient coping was associated with low T-cell activity.  相似文献   
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