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31.
Not having a variance estimator is a seriously weak point of a sampling design from a practical perspective. This paper provides unbiased variance estimators for several sampling designs based on inverse sampling, both with and without an adaptive component. It proposes a new design, which is called the general inverse sampling design, that avoids sampling an infeasibly large number of units. The paper provide estimators for this design as well as its adaptive modification. A simple artificial example is used to demonstrate the computations. The adaptive and non‐adaptive designs are compared using simulations based on real data sets. The results indicate that, for appropriate populations, the adaptive version can have a substantial variance reduction compared with the non‐adaptive version. Also, adaptive general inverse sampling with a limitation on the initial sample size has a greater variance reduction than without the limitation.  相似文献   
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Disabled people are excluded in various ways from a wide range of social privileges, activities and institutions. Voluntary and charitable organisations promote themselves as champions of disabled people in their struggle for access to the ordinary choices and opportunities of everyday life. This paper reports the findings of an empirical study which demonstrate that in voluntary agencies governed by able-bodied people, disabled people are excluded from positions of power and influence, and they experience the same sorts of barriers and constraints as those with which they are confronted in the wider world. Furthermore, the development of agencies governed by disabled people themselves is constrained by their lack of access to money, staff and other resources.  相似文献   
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Tax-exempt, non-profit organisations represent a significant and growing sector within the US economy. Between 1975 and 1990, assets of tax-exempt organisations increased in real terms by over 150 per cent while the revenue increased by over 227 per cent. This compares to a growth in real GDP of 52 per cent over the same period. A variety of tax policy issues on tax-exempt organisations and the non-profit sector can be addressed using several sources of data collected by the IRS from federal information and tax returns of exempt organisations. The Statistics of Income (SOI) Division, using sample data, conducts studies of many of the different components of the tax-exempt sector, including non-profit charitable organisations, organisations exempt under sections 501(c)(4)-(c)(9), private foundations and 4947(a) charitable trusts, and the unrelated business income of tax-exempt organisations. Income statement, balance sheet and other financial data, as well as a great amount of non-financial information, are collected in these SOI studies. The primary purposes of this article are: first, to document the role of the non-profit sector in the US economy and the evolving growth and change within the sector from the mid-1970s through to the present; and, second, to describe the ongoing SOI studies of tax-exempt organisations, the products and services available through SOI, and the future statistical plans at SOI for data collection and analysis of tax-exempt organisations and the non-profit sector.  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   
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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   
39.
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   
40.
This paper argues that the generally-held belief that there was no population policy in Great Britain during its fertility transition is incorrect. There were, in fact, clear and implicit and explicit policies in place by the early 19th Century which aimed at reducing population growth. These were negative, involving elimination of family allowances (the famous Poor Laws), and also positive, through subsidised emigration and ``transportation' of felons to the colonies. Moreover, a changed ``ideation' on the part of the nation's political, intellectual and spiritual leaders, changed norms about marriage and child-bearing, raising sharply the perceived economic and psychic cost of children. Lacking acceptable means to control pregnancies, many working class women resorted to abortion, infanticide and child abandonment to reduce their family size. The policy's actual impact on overall fertility is uncertain but it did constitute a deliberate attempt by society to affect demographic behaviour and outcomes.  相似文献   
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