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31.
流动人口计划生育工作是我国计划生育工作的两大难点之一。要提高流动人口计划生育管理水平,必须建立科学的指标体系来规范流动人口计生管理。本文结合实践,论述流动人口计生管理工作指标体系设置原则,统计口径,以及管理质量考核评估方法和内容。  相似文献   
32.
Each state has the power to establish its own policy and laws relating to child custody determination. The number of single-parent families with children that are headed by fathers has been growing in the United States. This paper explores the extent of cross-state variation in the prevalence in father-only families in 1990, and the extent to which there was cross-state variation in the increase in father-only families in the 1980s. The 1980 and 1990 Public Use Microdata Samples (PUMS) drawn from the US decennial censuses are used. Decomposition analyses of growth indicate that increases in the number of father-only families occurred across all states during this period, but at varying rates. The primary reason for the increase in most states is an increase in the proportion of ever-married single-parent families that are headed by a father. It is for these families that are headed by divorced or separated parents that state policy relating to child custody determination is most relevant.  相似文献   
33.
A heteroscedastic regression based on the odd log-logistic Marshall–Olkin normal (OLLMON) distribution is defined by extending previous models. Some structural properties of this distribution are presented. The estimation of the parameters is addressed by maximum likelihood. For different parameter settings, sample sizes and some scenarios, various simulations investigate the performance of the heteroscedastic OLLMON regression. We use residual analysis to detect influential observations and to check the model assumptions. The new regression explains the mass loss of different wood species in civil construction in Brazil.  相似文献   
34.
家庭托育点的规范化对婴幼儿健康成长至关重要。通过文献收集和访谈获得既往管理举措和当前试点政策,运用政策工具进行分析和总结,探究管理家庭托育点的背景、对象和措施。结果表明:家庭托育点因经济优势而被纳入管理,现有征求意见稿管理对象偏向小规模邻托,但试点和市场偏向较大收托规模;消防审查依托既有消防验收,师资准入要求偏低,质量监管依靠政府。管理建议:应根据收托规模区分小型和大型家庭托育点开展试点;完善三方协同的管理架构,设定专门空间环境要求,提高师资准入要求,建立综合质量监管。  相似文献   
35.
In-depth semi-structured interviews with 30 parents of children living with relatives in informal kinship care arrangements revealed the parents' views of the reasons for the informal kinship care arrangements, quality of their relationships with the children and their caregivers, their current and future roles in their children's lives, feelings experienced when with and away from the children, positive and negative aspects of kinship care, future goals and dreams for their children, and their assessments of their own strengths and challenges. Results of these interviews suggest several implications for social work practice and research.  相似文献   
36.
We consider a set of data from 80 stations in the Venezuelan state of Guárico consisting of accumulated monthly rainfall in a time span of 16 years. The problem of modelling rainfall accumulated over fixed periods of time and recorded at meteorological stations at different sites is studied by using a model based on the assumption that the data follow a truncated and transformed multivariate normal distribution. The spatial correlation is modelled by using an exponentially decreasing correlation function and an interpolating surface for the means. Missing data and dry periods are handled within a Markov chain Monte Carlo framework using latent variables. We estimate the amount of rainfall as well as the probability of a dry period by using the predictive density of the data. We considered a model based on a full second-degree polynomial over the spatial co-ordinates as well as the first two Fourier harmonics to describe the variability during the year. Predictive inferences on the data show very realistic results, capturing the typical rainfall variability in time and space for that region. Important extensions of the model are also discussed.  相似文献   
37.
This paper characterizes the family of Normal distributions within the class of exponential families of distributions, via the structure of the bias of the maximum likelihood estimator Θ n of the canonical parameter Θ . More specifically, when E θ ( Θ n ) – Θ = (1/ n ) Q ( Θ ) + o (1/ n ), the equality Q ( Θ ) = 0 proves to be a property of the Normal distribution only. The same conclusion is obtained for the one-dimensional case bt assuming that Q ( Θ ) is a polynomial of Θ .  相似文献   
38.
The Bayes estimators of the Gini index, the mean income and the proportion of the population living below a prescribed income level are obtained in this paper on the basis of censored income data from a pareto income distribution. The said estimators are obtained under the assumptions of a two-parameter exponential prior distribution and the usual squared error loss function. This work is also extended to the case when the income data are grouped and the exact incomes for the individuals in the population are not available. The method for the assessment of the hyperparameters is also outlined. Finally, the results are generalized for the doubly truncated gamma prior distribution. Now deceased.  相似文献   
39.
We show the second-order relative accuracy, on bounded sets, of the Studentized bootstrap, exponentially tilted bootstrap and nonparametric likelihood tilted bootstrap, for means and smooth functions of means. We also consider the relative errors for larger deviations. Our method exploits certain connections between Edgeworth and saddlepoint approximations to simplify the computations.  相似文献   
40.
指数族分布是一类应用广泛的分布类,包括了泊松分布、Gamma分布、Beta分布、二项分布等常见分布.在非寿险中,索赔额或索赔次数过程常常被假定服从指数族分布,由于风险的非齐次性,指数族分布中的参数θ也为随机变量,假定服从指数族共轭先验分布.此时风险参数的估计落入了Bayes框架,风险参数θ的Bayes估计被表达“信度”形式.然而,在实际运用中,由于先验分布与样本分布中仍然含有结构参数,根据样本的边际分布的似然函数估计结构参数,从而获得风险参数的经验Bayes估计,最后证明了该经验Bayes估计是渐近最优的.  相似文献   
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