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91.
Regina Thompson Paul H. Templet John K. Gamman Scott T. McCleary Margaret A. Reams 《Risk analysis》1994,14(5):857-861
The goal of Louisiana's 1990–1991 comparative risk project, also called the Louisiana Environmental Action Plan (LEAP), was to incorporate risk assessment into state environmental planning and policymaking. Scientists, government officials, and citizens were brought together to estimate the relative risk to human health, natural resources, and quality of life posed by 33 selected environmental issues. The issues were then ranked according to their relative estimated risks. It was hoped that this ranking of "comparative risks" would enable state policymakers to target the most important environmental problems and allocate scarce public resources more rationally and efficiently. As a result of the project, the governor issued an Executive Order forming a permanent Public Advisory Committee to continue this type of comparative risk assessment in Louisiana. 相似文献
92.
Abstract The objective of this study is to examine female labor force participation and its determinants in rural and urban China. The sociological literature has demonstrated that participation tends to increase in urban and industrialized places where women have higher levels of education and fewer children, where more workers are engaged in service pursuits, and where family structure is less traditional. With the use of data on counties and cities (N = 2,377) from the I-percent sample of the 1982 census of the People's Republic of China, it was found that female labor force participation is likely to rise in areas with increased agricultural employment, educational levels, proportion of female-headed households, and higher male-to-female sex ratios. Both the size of the service sector and the fertility rate had negligible effects on female labor force participation. Although, on average, rural places have slightly higher levels of female labor force participation, when other variables are controlled, urban places have a higher rate of female participation. In addition, the findings suggest that market factors (i.e., education) are more likely to determine the rate of female labor force participation in urban areas; whereas demographic and social factors (i.e., sex ratio and household structure) play a more important role in explaining the female labor force participation in rural counties. 相似文献
93.
Since children, particularly daughters, are among the most important sources of help and support for older Americans, it has been suggested that women's increasing employment will affect filial relations. Empirical evidence on this issue is inconsistent, in part due to the use of nonprobability samples. Few studies have measured effects for men. We attempt to broaden the scope of this question beyond help to the frail elderly by asking whether employment affects filial relations in general. We examine effects of hours employed on telephone contact, visiting, feelings of closeness, filial attitudes, and assistance to biological parents, for an area probability sample of men and women over 40. There are no effects of employment for men or women on contact, closeness, or assistance. For the vast majority of this population sample, contact and assistance involve few hours per week, and thus do not seem to conflict with employment. 相似文献
94.
Bhaswati Ganguli John Staudenmayer M.P. Wand 《Australian & New Zealand Journal of Statistics》2005,47(2):193-202
This paper develops a likelihood‐based method for fitting additive models in the presence of measurement error. It formulates the additive model using the linear mixed model representation of penalized splines. In the presence of a structural measurement error model, the resulting likelihood involves intractable integrals, and a Monte Carlo expectation maximization strategy is developed for obtaining estimates. The method's performance is illustrated with a simulation study. 相似文献
95.
Religious affiliation and the family 总被引:1,自引:0,他引:1
The process of religious affiliation is mediated by institutions such as the family, which provide a network of ties to the public sphere. Variations in the likelihood of those with no religious affiliation in high school (N=900) becoming church members by the time they reach 30 are explained in terms of a combination of individual attributes, such as educational and spatial mobility, and changes in structural location, such as the transition to marital and parental status. Panel data from the Career Development Study show that women's chances of affiliation are more affected than are men's by parents' religious homogamy, getting married, and having children. 相似文献
96.
The EM algorithm is a popular method for maximizing a likelihood in the presence of incomplete data. When the likelihood has multiple local maxima, the parameter space can be partitioned into domains of convergence, one for each local maximum. In this paper we investigate these domains for the location family generated by the t-distribution. We show that, perhaps somewhat surprisingly, these domains need not be connected sets. As an extreme case we give an example of a domain which consists of an infinite union of disjoint open intervals. Thus the convergence behaviour of the EM algorithm can be quite sensitive to the starting point. 相似文献
97.
John C. Harsanyi 《Social Choice and Welfare》1995,12(4):319-333
Ethics can be divided into a theory of prudential values and a theory of morality in a narrower sense. My paper proposes a utilitarian — a rule-utilitarian — theory of morality. But it deviates from most of the utilitarian tradition by rejecting the hedonistic and subjectivistic accounts of prudential values favored by many utilitarian writers. While economists tend to define people's utility levels in terms of their actual preferences, ethics must define them in terms of their informed preferences. To prefer A over B does not mean to have a stronger desire for A than for B. Rather, it means to regard one's access to A as being more important than one's access to B. Even though different people often have quite different preferences, their basic desires seem to be much the same. We must choose our moral rules, and our society's moral code as a whole, by their social utility. An important factor in determining their social utility are their expectation effects. Unlike the rule — utilitarian more code, the act — utilitarian moral code would be unable to give proper weight to these expectation effects. It would also unduly restrict our individual freedom. Finally, I shall argue against Kant that morality is primarily a servant of many other human values rather than itself the highest value of human life. 相似文献
98.
Debates about regulatory efforts to monitor the delivery of health and long-term care have become commonplace in health policy. Efforts to examine the key assumptions underlying the current regulatory strategies have been limited, however. Using the board and care industry as an example, this article examines how ideology influences the regulatory strategy developed. Three ideological perspectives-a free-market approach, a market correction strategy, and a critical policy framework-are reviewed in the context of efforts to regulate board and care homes in the United States. Differences in approaches to regulating board and care are presented for each of the major perspectives. 相似文献
99.
Edward A. Hanna Ph.D. 《Clinical Social Work Journal》1993,21(3):283-300
This paper explores an unusual and innovative application of psychodynamically oriented clinical social work method to the sports area. The coach of a national Olympics team requested a clinical consultation because he suspected that there might be psychosocial reasons why a certain number of world class atheletes he was coaching were not performing up to their full potential. 相似文献
100.
The skin is a route of exposure that needs to be considered when conducting a risk assessment. It is necessary to identify the potential for dermal penetration by a chemical as well as to determine the overall importance of the dermal route of exposure as compared with inhalation or oral routes of exposure. The physical state of the chemical, vapor or liquid, the concentration, neat or dilute, and the vehicle, lipid or aqueous, is also important. Dermal risk is related to the product of the amounts of penetration and toxicity. Toxicity involves local effects on the skin itself and the potential for systemic effects. Dermal penetration is described in large part by the permeability constant. When permeability constants are not known, partition coefficients can be used to estimate a chemical's potential to permeate the skin. With these concepts in mind, a tiered approach is proposed for dermal risk assessment. A key first step is the determination of a skin-to-air or skin-to-medium partition coefficient to estimate a potential for dermal absorption. Building a physiologically-based pharmacokinetic (PBPK) model is another step in the tiered approach and is useful prior to classical in vivo toxicity tests. A PBPK model can be used to determine a permeability constant for a chemical as well as to show the distribution of the chemical systemically. A detailed understanding of species differences in the structure and function of the skin and how they relate to differences in penetration rates is necessary in order to extrapolate animal data from PBPK models to the human. A study is in progress to examine anatomical differences for four species. 相似文献