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901.
Suppose X1, X2, ..., Xm is a random sample of size m from a population with probability density function f(x), x>0 and let X1,m<...m,m be the corresponding order statistics. We assume m as an integer valued random variable with P(m=k)=p(1?p)k?1, k=1, 2, ... and 0 and n X1,n for fixed n characterizes the exponential distribution. In this paper we prove that under the assumption of monotone hazard rate the identical distribution of and (n?r+1) (Xr,n?Xr?1,n) for some fixed r and n with 1≤r≤n, n≥2, X0,n=0, characterizes the exponential distribution. Under the assumption of monotone hazard rate the conjecture of Kakosyan, Klebanov and Melamed follows from the above result with r=1.  相似文献   
902.
In this paper the timing of maternity is estimated by a hazard model. The novel aspect of this paper is that it is shown that wages and total household labor income have a significant effect on the timing of maternity. Both the wage rate of the woman and the wage rate of the husband have a negative effect on the timing of maternity. Total household labor income increases the probability of having a child at an earlier age. Calculated elasticities show that the timing of maternity is relatively elastic with respect to wage rates. However, the elasticities of the decision whether or not to have children altogether are much smaller. Women working in the labor market delay the timing of maternity compared to non-participating women. Attending school has the same effect. Until the age of 28 the maternity hazard increases with age, after that it decreases.We benefited from comments on previous drafts by Siv Gustafsson, Joop Hartog, Peter Kee, Herriette Maassen van den Brink, Eddie Mekkelholt, Joop Odink, Hessel Oosterbeek, Hans van Ophem, Gusta Renes, Andre Voskamp, two anonymous referees, and the Managing Editor of this Journal. This paper is a revised version of a paper presented at the third annual meeting of the European Society for Population Economics, Paris, June 1989. The usual disclaimer applies.  相似文献   
903.
Elective single mothers are adult, unmarried women who intentionally become mothers. This study utilized longitudinal data about 17 Caucasian, elective single mothers and their children to identify fathers' roles in these families, and to understand children's views of their fathers. These single mothers and their children resided for the first six years of the children's lives in father-absent households. By age six, most of the children had ghost fathers, whom they had never met or knew little about. The data suggest that the father often becomes a family secret, and that children may blame themselves for their fathers' absence.  相似文献   
904.
905.
A paradox currently exists regarding legal sports gambling in North America: various forms are flourishing in Nevada, Oregon, and several Canadian provinces, while at the same time the United States Congress is conducting hearings on two bills that would prohibit any new state-sponsored sports gambling initiatives. This study examines the issue of why some jurisdictions are enthusiastic about legal sports gambling while others strongly resist the concept. In reviewing these divergent viewpoints, a case study of the newfledged Canadian Sport Select gambling format is presented. This example is used to highly the perils and payoffs of a typical state-sponsored sports gambling scheme, with a view toward broadening our understanding of how they work and how they might be fairer to the public.  相似文献   
906.
Social workers are required to collect a considerable amount of personal information about clients and their families which may be unrelated to direct clinical work. Administrators often use this for the purpose of payment, service documentation, agency planning, and accountability. The worker's concern about the appropriateness of collecting this data may result in poor compliance or even falsification of information. In a survey of Minnesota social workers, noncompliance with data collection requirements was substantial. The authors also found a significant degree of conflict about privacy and confidentiality issues. These findings suggest a basis of concern for those who must rely on accurate data for administrative planning.  相似文献   
907.
The author argues that the burden of proof for the safety and efficacy of some medical devices properly lies with the manufacturers of the devices and with the providers who use them. The controversy over breast implants is used as a case for this shift in the burden of proof of safety and effectiveness.  相似文献   
908.
College newspapers are a powerful but underutilized medium for educating students on health issues, including those related to drug and alcohol use on campus. Editors of these publications are in a position to wield significant influence among their readers. In addition to communicating factual information about the prevalence and impact of substance use among college students, editors can use the press to advocate changes in students' attitudes and behaviors and in college or community policies that affect substance use. A pilot conference was held to help New England college newspaper editors perceive the importance of their role in educating their peers about substance use and other health-related issues, and to offer concrete suggestions as to how they can incorporate these topics into an "activist" campus press.  相似文献   
909.
This is a report from a conference held in Tokyo, Japan, in 1991 on the economic aspects of labor mobility in Asia. The authors briefly describe selected papers given at the conference and outline conference topics. A list of participants is included. (SUMMARY IN FRE AND SPA)  相似文献   
910.
"This article shows that an analysis of the impacts of immigration [in Western Europe] has to be divided into allocational and distributional aspects. From an allocational point of view, like free trade in goods, services and capital, migration is welfare-improving as long as marginal productivities of labor are not equalized worldwide. From a distributional point of view, however, the immigration society has to bear the effects of sharing its common public goods and its social values with the new immigrants. Free immigration will only be allowed if the allocational welfare gains exceed the distributional welfare losses. According to this rule of thumb, a guideline for an efficient migration policy is sketched."  相似文献   
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