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81.
本文为第三届“文化与城市可持续发展”国际会议的主题发言。本文介绍了会议背景 ,论述了文化及其与可持续发展的关系 ,都市化进程及其发展方向等问题 ,并着重阐述了本次会议的主题即“城市可持续发展中的文化指标” ,确立了本次会议的总体基调和基本政策  相似文献   
82.
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   
83.
Racial differences in urban neighboring   总被引:2,自引:0,他引:2  
Despite mixed expectations generated by existing theories and evidence, this analysis documents clear racial differences in urban neighboring behavior. Using data from a survey of Nashville, Tennessee, residents, we show that blacks interact with their neighbors more often than whites do, and in a greater variety of ways. The only noteworthy similarity between the two groups is the positive impact of neighboring on feelings of community affect. Overall, our results support the view that neighbor relations — like other kinds of informal participation — have helped blacks cope with constrained social opportunities and provided them with access to resources unavailable through formal institutional channels.Revised version of a paper presented at the annual meeting of the American Sociological Association, San Francisco, August 1989.  相似文献   
84.
Differential participation after recruitment remains a black box in the social-movement and voluntary-association literatures. This paper identifies several dimensions of membership participation in a professional social-movement organization (SMO) with a national membership and analyzes the determinants of differential involvement in these forms. In general, members' ideological beliefs, social and organizational ties, perceptions about their SMO, and communication with SMO officials all predict participation across the various forms. Our findings extend previous work on differential participation in three ways. First, we statistically isolate cultural dimensions of postrecruitment participation and, in so doing, complement recent ethnographic research. Second, our findings suggest that the distinct dimensions of external and internal participation found by Knoke (1988) in a national sample of voluntary associations may not generalize to national SMOs studied individually. Third, our results indicate that models combining ideological and microstructural factors should explain the multiple forms of participation in SMOs lacking these distinct dimensions.  相似文献   
85.
86.
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   
87.
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   
88.
The study investigates European American and Taiwanese grandmothers’ folk theories of childrearing and self‐esteem, building on an earlier comparison of mothers from the same families. Adopting methods that privilege local meanings, we bring grandmothers’ voices into the conversation about childrearing, thereby contributing to a deeper understanding of intergenerational nuances in folk theories. In each cultural case, 16 grandmothers of 3‐year‐olds participated in in‐depth interviews that were customized according to local communicative norms. Although self‐esteem emerged as a central organizing concept in the folk theories of European American mothers, grandmothers spoke in two voices, either echoing their daughters or invoking a counter‐discourse of wariness towards self‐esteem. By contrast, Taiwanese mothers and grandmothers resembled one another—but differed from their American counterparts—in treating self‐esteem as peripheral in childrearing. Results contribute to the growing consensus that self‐esteem is a culture‐specific childrearing goal and suggest that the European American tendency to valorize self‐esteem varies by generation.  相似文献   
89.
Conditional cash transfers are a departure from more traditional approaches to social assistance that represents an innovative and increasingly popular channel for the delivery of social services. Conditional cash transfers provide money to poor families contingent upon certain behaviour, usually investments in human capital such as sending children to school or bringing them to health centres on a regular basis. They seek both to address traditional short-term income support objectives and promote the longer-term accumulation of human capital by serving as a demand-side complement to the supply of health and education services. Evaluation results reveal that this innovative design has been quite successful in addressing many of the failures in delivering social assistance such as poor poverty targeting, disincentive effects and limited welfare impacts. There is clear evidence of success from the first generation of programmes in Brazil, Colombia, Mexico and Nicaragua in increasing enrolment rates, improving preventive healthcare and raising household consumption. Despite this promising evidence, many questions remain unanswered about conditional cash transfer programmes, including the replicability of their success under different  相似文献   
90.
Projecting losses associated with hurricanes is a complex and difficult undertaking that is wrought with uncertainties. Hurricane Charley, which struck southwest Florida on August 13, 2004, illustrates the uncertainty of forecasting damages from these storms. Due to shifts in the track and the rapid intensification of the storm, real-time estimates grew from 2 to 3 billion dollars in losses late on August 12 to a peak of 50 billion dollars for a brief time as the storm appeared to be headed for the Tampa Bay area. The storm hit the resort areas of Charlotte Harbor near Punta Gorda and then went on to Orlando in the central part of the state, with early poststorm estimates converging on a damage estimate in the 28 to 31 billion dollars range. Comparable damage to central Florida had not been seen since Hurricane Donna in 1960. The Florida Commission on Hurricane Loss Projection Methodology (FCHLPM) has recognized the role of computer models in projecting losses from hurricanes. The FCHLPM established a professional team to perform onsite (confidential) audits of computer models developed by several different companies in the United States that seek to have their models approved for use in insurance rate filings in Florida. The team's members represent the fields of actuarial science, computer science, meteorology, statistics, and wind and structural engineering. An important part of the auditing process requires uncertainty and sensitivity analyses to be performed with the applicant's proprietary model. To influence future such analyses, an uncertainty and sensitivity analysis has been completed for loss projections arising from use of a Holland B parameter hurricane wind field model. Uncertainty analysis quantifies the expected percentage reduction in the uncertainty of wind speed and loss that is attributable to each of the input variables.  相似文献   
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