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41.
Abstract It is well recognized that the informal economy—unregulated economic activities that generate real or in-kind income—features prominently in the day-to-day lives of many in the developing world. Researchers have begun to explore the informal economy in developed countries but this work has focussed primarily on urban areas to the neglect of rural areas. In this paper the nature and correlates of informal work in nonmetropolitan Pennsylvania are described through an analysis of survey data on 505 families. Results indicate that participation in informal activities is widespread, is not more typical of the poor, does not contribute greatly to family income on average but does help many poor families weather difficult economic times, is both economically and noneconomically motivated, and, net of other sociodemographic variables, is positively related to rurality of residence and formal labor supply.  相似文献   
42.
The evolving democracies of Eastern Europe and the former USSR republics are keenly interested in establishing charities. They have little law on this issue because their former governments did not encourage the development of charities. This article compares US and English regulation of charities and proposes a regulatory framework based on what the authors believe are the best attributes of both. Although the framework is based on the common law system, it can be adapted to the civil law systems of the Eastern European nations and the former USSR republics. The article includes such issues as developing a body of law, tax relief and creating a regulatory agency.Mr Hopkins is a lawyer with Powers, Pyles & Sutter, 1275 Pennsylvania Ave., N.W., Washington, D.C. 20007, and author ofThe Law of Tax-Exempt Organizations (1992a).Ms Moore is also a lawyer, 5908 N. 35th St., Arlington, Virginia 22207.The authors would like to thank Mssrs Kersi Shroff and Stephen F. Clarke, Senior Legal Specialists, American-British Law Division, Library of Congress, and Mr. William H. Morris, an attorney at Steptoe & Johnson, Washington, D.C., for their kind assistance during the researching of this article.  相似文献   
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Martina Löw 《Soziologie》2006,35(2):222-224
Ohne Zusammenfassung  相似文献   
46.
Low dose risk estimation via simultaneous statistical inferences   总被引:2,自引:0,他引:2  
Summary.  The paper develops and studies simultaneous confidence bounds that are useful for making low dose inferences in quantitative risk analysis. Application is intended for risk assessment studies where human, animal or ecological data are used to set safe low dose levels of a toxic agent, but where study information is limited to high dose levels of the agent. Methods are derived for estimating simultaneous, one-sided, upper confidence limits on risk for end points measured on a continuous scale. From the simultaneous confidence bounds, lower confidence limits on the dose that is associated with a particular risk (often referred to as a bench-mark dose ) are calculated. An important feature of the simultaneous construction is that any inferences that are based on inverting the simultaneous confidence bounds apply automatically to inverse bounds on the bench-mark dose.  相似文献   
47.
The well-known chi-squared goodness-of-fit test for a multinomial distribution is generally biased when the observations are subject to misclassification. In Pardo and Zografos (2000) the problem was considered using a double sampling scheme and ø-divergence test statistics. A new problem appears if the null hypothesis is not simple because it is necessary to give estimators for the unknown parameters. In this paper the minimum ø-divergence estimators are considered and some of their properties are established. The proposed ø-divergence test statistics are obtained by calculating ø-divergences between probability density functions and by replacing parameters by their minimum ø-divergence estimators in the derived expressions. Asymptotic distributions of the new test statistics are also obtained. The testing procedure is illustrated with an example.  相似文献   
48.
Summary.  Factor analysis is a powerful tool to identify the common characteristics among a set of variables that are measured on a continuous scale. In the context of factor analysis for non-continuous-type data, most applications are restricted to item response data only. We extend the factor model to accommodate ranked data. The Monte Carlo expectation–maximization algorithm is used for parameter estimation at which the E-step is implemented via the Gibbs sampler. An analysis based on both complete and incomplete ranked data (e.g. rank the top q out of k items) is considered. Estimation of the factor scores is also discussed. The method proposed is applied to analyse a set of incomplete ranked data that were obtained from a survey that was carried out in GuangZhou, a major city in mainland China, to investigate the factors affecting people's attitude towards choosing jobs.  相似文献   
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用Ostwald粘度计测定液体粘度系数的实验是医学院校物理实验课普遍开设的基本实验之一,这套装置为本实验室自行设计制作,并在本实验室使用.此装置具有实验结果误差小,操作方便,不易损坏仪器,取料容易,观测视角广阔,体积狭小,结构简单紧凑等特点,文中具体介绍了粘度计保护盒的制作、安装及整套实验装置的使用方法.  相似文献   
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