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891.
M. Ahsanullah 《Statistical Papers》1988,29(1):151-157
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.
896.
Liebig PS 《Journal of aging & social policy》1992,4(1-2):17-33
Shifts in the American political landscape during the 1980s had impacts on aging policy and on the behavior of aging interest groups through that decade. But perhaps even more important are the likely effects of those changes on aging policy and on the roles of age-related groups in the 1990s--and probably beyond. First, some of the major policy trends of the 1980s are sketched out, especially the renewed emphasis on federalism. Then, an assessment of their effects on aging policy and aging interest groups is provided. Next, a rationale for focusing on state-level policy and a discussion of current aging interest-group mobilization at the state level are presented. Last, the prospects for aging interest-group influence in the 1990s--a period in which the prior decade's emphasis on dual federalism is likely to continue--is addressed. 相似文献
897.
Garry J. Smith Ph.D. 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》1992,8(4):331-349
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
898.
899.
The China Population information Centre (CPIC), set up in May 1980, is a national institution for population information research under the State Family Planning Commission. Its main functions are to 1) collect, process, and distribute and foreign materials on population and family planning; 2) collect, tabulate, and analyze population and family planning data; 3) keep abreast of new population and family planning developments within and outside the country; 4) edit and publish information materials; and 5) provide information users with diversified services. The CPIC has 8 operational units: 1) the Library, 2) the Statistics Division, 3) the 1st Information Research Division, 4) the 2nd Information Research Division, 5) the Editorial Division, 6) the Translation Division, 7) the Computer Division, and 8) the Technical Support Division. 相似文献
900.
United Nations. Economic Commission for Africa 《International migration (Geneva, Switzerland)》1986,24(1):197-212
A very large number of skilled Africans are found to be operating in the developed industrialized countries of the West at a time when their national economies are crying out for their services. Ways must be found to return as many of these skilled Africans as possible to the African economy. This out-migration or brain drain has a number of causes, including: 1) real incomes in Africa have been on the decline in the past several years while prices were constantly rising. Professional and salaried workers seek employment in other countries that pay much higher salaries. 2) Promotion on criteria other than merit is common in Africa and diligence and high productivity are not often rewarded. 3) Political interference frustrates public services professionals; they are rendered unable to use their professional judgement in making decisions that affect the economic and social fabric. 4) The inadequacy of higher education facilities and opportunities in African countries encourages the brightest and best qualified Africans to go to Western Europe and North America for school; they tend not to return after graduation. 5) Political upheavals and general instability contribute to feelings of individual insecurity, sending Africans to seek sanctuary in more politically stable and less repressive environments. Actions needed to control this out-migration include: 1) incentive systems should be reviewed with a view to providing realistic levels of renumeration and working conditions should be made to promote job satisfaction and self-actualization. 2) Capacities and capabilities should be strengthened so as to ensure that production of goods and services becomes indigenized and that the development and operation of institutions emanates from within the continent. 3) Educational services should be expanded and improved to obviate the need for large numbers of Africans to seek educational opportunities abroad. 相似文献