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891.
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   
892.
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   
893.
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   
894.
895.
Between 1987 and 1990, the Robert Wood Johnson Foundation funded six service credit banking demonstration programs among the elderly in which participants delivered services in return for credits, entitling them to later service. This evaluation of the demonstrations found that these six sites successfully attracted elders for the delivery of household support services to a relatively old, frail population with potentially limited social networks. Evidence on the significance of the "credit" in attracting volunteers was mixed, but the programs have attracted new volunteers, and have not substituted for other volunteer activities. Program development has entailed considerable staff investment in volunteer support; programs are better understood as community membership organizations than as mechanical exchanges.  相似文献   
896.
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   
897.
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   
898.
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   
899.
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   
900.
The All-China Women's Federation (WF) is a non-governmental organization of women and the highest leading body of the Women's Federations at all levels of the country. The WFS spare no efforts to do women good turns, work for their well-being and serve them wholeheartedly. The WFs are actively organizing women to learn to read and write and to acquire skills. The WFs play a role in protecting and education women, and in struggling for the safeguard of the legitimate rights of women and children. The WFs at all levels have been showing great concern for family planning. Finally, the WFs devote much attention to the training of women cadres, and to the improvement of their cultural level and working ability.  相似文献   
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