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991.
Differences in population characteristics among the administrative districts of Poland are analyzed. The characteristics examined include density, place of employment, urban population growth, population employed in agriculture, and migration.  相似文献   
992.
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   
993.
It is shown that when a parameter lying in a sufficiently small interval is to be estimated in a family of uniform distributions, a two point prior is least favourable under squared error loss. The unique Bayes estimator with respect to this prior is minimax. The Γ-minimax estimator is derived for sets Γ of priors consisting of all priors that give fixed probabilities to two specified subintervals of the parameter space if a two point prior is least favourable in Γ.  相似文献   
994.
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   
995.
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   
996.
There is growing recognition in the nonprofit field that the executive director has a key role in determining whether the board of directors will function effectively. To aid executives in this vital role, two recent studies defined a "good board" from the point of view of two samples of executive directors of community agencies, then sought factors related to board performance as measured by this definition. In interviews, executives whose boards scored higher than their peers on this performance measurement related how they work with their boards in such areas as recruitment of new members, financial management, fundraising, and leadership development.  相似文献   
997.
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   
998.
The paper provides an empirical analysis of saving and consumption choices of the elderly in Germany, based on the German income and expenditure surveys 1978 and 1983. Main feature of these data is the large sample size making it possible to analyze saving and consumption patterns of the very old (aged 75 and above).The observed age-consumption profiles are very different from those predicted by the pure life-cycle theory. Although wealth is declining between age 60 and 70, it increases again after 70, such that the very old have the highest savings rates among all age groups and accumulate wealth rather than decumulate it. These profiles are not confounded by cohort effects and mortality differences. The corresponding expenditure data suggest the following explanation: due to the generous German pension system and the almost complete coverage of health expenses by the mandatory health insurance in Germany, the declining consumption n very old age cannot exhaust the annuity income of the elderly such that wealth is being accumulated in old age.Research in this paper was supported by the National Institute on Aging, grant no. 3 PO1 AG05842-01. I appreciate the helpful comments by Doug Bernheim, Angus Deaton, Daniel McFadden, Jonathan Skinner, Konrad 'Stahl and David Wise, and two anonymous referees. I am indebted to Hermann Buslei and Johannes Velling who provided most valuable and able assistance.  相似文献   
999.
Adolescents' social behaviors remain a mystery to parks and recreation providers. Adolescence is a "high-risk" time for all youth in terms of experimenting with potentially health-compromising behavior, whether alcohol, drugs, or sex. Most of these antisocial behaviors occur during adolescents' leisure time. These inferences gave impetus to this research effort. The study was designed to ascertain information on adolescents' preferences for pleasure: drugs or recreation. Data were collected from a sample of 100 high school students from a medium-sized college town, and 100 students from a rural town in Florida. Findings revealed four statistically significant associations in the motives or pleasures sought in recreation and in drug behaviors: "enhancement of popularity," "provision of a means for self-discovery," "achievement of personal goal," and means to rebel against parents. In reference to the latter motive, findings revealed that neither drugs nor recreation were used to rebel against parents. Findings also provide documentation of the value of recreation in insulating adolescents against many of the stressors of contemporary life.  相似文献   
1000.
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   
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