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101.
102.
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   
103.
I model a competitive insurance market with both moral hazard and adverse selection, and analyze the effect on welfare when both problems are present simultaneously. An examination of the interaction between these two problems leads to two hypotheses. First, the nature of the equilibrium contracts is such that each problem partially offsets the welfare loss associated with the other. And second, the degree to which this occurs increases as agents become more heterogeneous. Simulation results overwhelmingly support both hypotheses.  相似文献   
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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   
106.
This paper estimates a simultaneous-equations model with public sector bargaining laws and union membership treated as jointly-determined variables. The extent of public sector unionization has a significant positive influence on the passage of prolabor bargaining legislation and bargaining legislation has strong, independent effects on the extent of public sector unionization. We gratefully acknowledge the research support provided by Minbo Kim and Parisun Chantonahom.  相似文献   
107.
张钧成先生是我国著名的林业历史学家.该文从林业史学科建设、林业史研究概况、中国古代林业通史、中国古代林业思想和传统文化、林业科技史和经济史、近现代林业史等研究领域,概述了张先生的学术成就,并回顾了张先生高尚的人生哲学和宝贵的治学经验.张先生的研究成果和治学经验,为我国林史学科的发展奠定了基础.  相似文献   
108.
109.
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   
110.
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   
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