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151.
The use of time for child care and housework among Swedish families is investigated. We allow the effect of children on child care and housework to vary by age of the child and also by whether the child is cared for outside the home or not. Our estimates allow us to compute the total cost of children in the form of the cost of time, and the cost of goods, services and housing.The result shows that time used for child care decreases sharply with the age of the child but this is not the case for time used for other housework. Considerable economies of scale is found to prevail for time used for child care. Child care outside the home reduces time use for other housework but the effect on time used for child care is quite small. For the average family time use cost make up more than half of total child cost. Our estimates indicate that decreased time use cost for children caused by care outside the home are not very different from a typical parental fee for public day care.This research was supported by a grant from the Swedish Council of Social Research (SFR). We thank Lennart Flood for useful comments on an earlier version.  相似文献   
152.
The authors outline demographic trends in Eastern Europe and Russia since 1970. Aspects considered include population size, birth rate and number of births, marriage and divorce, death rate, infant mortality, natural increase, sex ratio, and life expectancy.  相似文献   
153.
154.
The success of the third sector depends on public confidence, and that confidence rests, in part, on holding managers, directors, and officers of nonprofits responsible for their conduct. This accountability can be accomplished by clearly defining the roles of these individuals and the stands that they are to uphold, and by providing channels for all interested to challenge uncontrolled activities. Though interest in this goal is unanimous, a debate exists over how to ensure oversight and accountability.  相似文献   
155.
Evolution strategies (ESs) are a special class of probabilistic, direct, global optimization methods. They are similar to genetic algorithms but work in continuous spaces and have the additional capability of self-adapting their major strategy parameters. This paper presents the most important features of ESs, namely their self-adaptation, as well as their robustness and potential for parallelization which they share with other evolutionary algorithms.Besides the early (1 + 1)-ES and its underlying theoretical results, the modern ( + )-ES and (, )-ES are presented with special emphasis on the self-adaptation of strategy parameters, a mechanism which enables the algorithm to evolve not only the object variables but also the characteristics of the probability distributions of normally distributed mutations. The self-adaptation property of the algorithm is also illustrated by an experimental example.The robustness of ESs is demonstrated for noisy fitness evaluations and by its application to discrete optimization problems, namely the travelling salesman problem (TSP).Finally, the paper concludes by summarizing existing work and general possibilities regarding the parallelization of evolution strategies and evolutionary algorithms in general.  相似文献   
156.
This paper considers the application of Stein-type estimation procedure for the coefficients in a linear regression model when data are available from replicated experiment. Two families of estimators characterized by a single scalar are proposed and their large sample asymptotic properties are derived. These are utilized for comparing the performances of the two estimators along with the conventional estimator and conditions for the superiority of one estimator over the other are deduced.  相似文献   
157.
"This article presents some of the latest available figures on illegal immigration in Japan, a process that did not assume significant proportions until the mid-1980s. It also discusses briefly the latest developments around 'immigration' policy--more precisely, the law on the entry and exit of aliens."  相似文献   
158.
Outdoor structured activities, such as Ropes Challenge Courses, are typically utilized as interventions for youth coming from urban settings. Evaluation of such programs is scanty at best. In this instance, the course experience is used as a prevention tool for high risk youth in a remote, rural setting of high unemployment, alcohol problems, and low income. The authors discuss the effectiveness of this approach, and the intended and unintended consequences for the rural community at large. The evaluation design relies on extensive qualitative methodology as well as quantitative methods to capture the unique nature of this rural project.  相似文献   
159.
This article examines the current trends of proliferation of commercial gaming, especially in the United States, in the context of the third wave of legalization of gambling that has been experienced since the founding of the nation. The author looks at the historic foundations of the spread of casino-style gambling, and notes the types of casino gaming that have led the way in the current expansion. He also points out why it is reasonable to expect that this wave too may come crashing down, as general acceptance of wide-spread casino gaming in America may indeed be short-lived.Gambling and the Law® is a registered trademark of I. Nelson Rose.  相似文献   
160.
The strategy of grounded theory: possibilities and problems   总被引:1,自引:0,他引:1  
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