A longitudinal study of depressiveness in children in public care

Rajhvajn Bulat L. A longitudinal study of depressiveness in children in public care Int J Soc Welfare 2010: 19: 412–423 © 2009 The Author, Journal compilation © 2009 Blackwell Publishing Ltd and the International Journal of Social Welfare. The aim of this article is to analyse the challenges involved when making longitudinal observations of depressiveness in children raised in public care. The first measurement comprised 375 children from children's homes and foster families; however, most of the results are based on an analysis of the 139 children who participated in both parts of the research. We used the Child Depression Inventory and the anxiety/depression subscales of Youth Self Report and Child Behaviour Checklist as measures of depressiveness. The comparison of results from the first and second measurements showed that depressiveness in children in public care decreased over time. Children who grew up in children homes were, in the first measurement, more depressed than those living in foster families, but after five years that difference had disappeared. Furthermore, decrease in depressiveness is predominantly associated with less frequent delinquent, aggressive or hyperactive behaviour, less withdrawal and better control over uncomfortable emotions.     

金融危机下中国创业投资“囚徒困境”演化研究

创业投资家和创业企业家的＂囚徒困境＂是制约中国创业投资进一步发展的主要障碍之一。对短期利益的追求和缺乏信任是造成中国创业投资＂囚徒困境＂的两个重要原因。在金融危机背景下,＂囚徒困境＂的演化将朝着有利于创业投资家的方向发展。金融危机虽然能改变博弈的结果,却未能改变＂囚徒困境＂的成因。     

基于主体功能区划自然保护区生态补偿机制之构建与完善

根据国家主体功能区划,自然保护区被界定为禁止开发区域,必然要对其科学有效地实施生态补偿;自然保护区生态补偿机制应当结合当前主体功能区划的政策导向,进行重新定位与构建。依据公共物品与外部性等理论,为缓解现实矛盾,需积极探索构建多元化融资渠道的保护区生态补偿机制,主要涉及政府与市场两种基本途径或机制范畴,合理安排相应的政策引导与制度创新。制度构建的关键在于加快自然保护区生态补偿的立法调整,无论是政府财政转移支付还是市场经济手段的生态补偿政策,都需要立法确定其方针原则、实施模式及机制。     

The empirical Bayes estimators of the parameter of the Poisson distribution with a conjugate gamma prior under Stein's loss function

For the hierarchical Poisson and gamma model, we calculate the Bayes posterior estimator of the parameter of the Poisson distribution under Stein's loss function which penalizes gross overestimation and gross underestimation equally and the corresponding Posterior Expected Stein's Loss (PESL). We also obtain the Bayes posterior estimator of the parameter under the squared error loss and the corresponding PESL. Moreover, we obtain the empirical Bayes estimators of the parameter of the Poisson distribution with a conjugate gamma prior by two methods. In numerical simulations, we have illustrated: The two inequalities of the Bayes posterior estimators and the PESLs; the moment estimators and the Maximum Likelihood Estimators (MLEs) are consistent estimators of the hyperparameters; the goodness-of-fit of the model to the simulated data. The numerical results indicate that the MLEs are better than the moment estimators when estimating the hyperparameters. Finally, we exploit the attendance data on 314 high school juniors from two urban high schools to illustrate our theoretical studies.     

Fitting competing risks data to bivariate Pareto models

This paper revisits two bivariate Pareto models for fitting competing risks data. The first model is the Frank copula model, and the second one is a bivariate Pareto model introduced by Sankaran and Nair (1993 Sankaran, P. G., and N. U. Nair. 1993. A bivariate Pareto model and its applications to reliability. Naval Research Logistics 40 (7):1013–1020. doi:10.1002/1520-6750(199312)40:7%3c1013::AID-NAV3220400711%3e3.0.CO;2-7.[Crossref], [Web of Science ®] , [Google Scholar]). We discuss the identifiability issues of these models and develop the maximum likelihood estimation procedures including their computational algorithms and model-diagnostic procedures. Simulations are conducted to examine the performance of the maximum likelihood estimation. Real data are analyzed for illustration.     

Bayesian Treatment of Model Uncertainty for Partially Applicable Models

This article discusses how analyst's or expert's beliefs on the credibility and quality of models can be assessed and incorporated into the uncertainty assessment of an unknown of interest. The proposed methodology is a specialization of the Bayesian framework for the assessment of model uncertainty presented in an earlier paper. This formalism treats models as sources of information in assessing the uncertainty of an unknown, and it allows the use of predictions from multiple models as well as experimental validation data about the models’ performances. In this article, the methodology is extended to incorporate additional types of information about the model, namely, subjective information in terms of credibility of the model and its applicability when it is used outside its intended domain of application. An example in the context of fire risk modeling is also provided.     

我国企业品牌定位的五层次研究

近年来中国企业的品牌建设取得了可喜的成绩,出现了许多优秀品牌,这些品牌凭借独特、合适的定位取得了成功。但企业在品牌定位方面存在许多误区,如把品牌定位看作产品定位、品牌定位模糊,缺乏差异性和明确的核心价值、品牌盲目延伸导致定位混淆等问题。因此,产品品牌定位必须树立正确的定位理念,应用正确的品牌定位方法。正确的品牌定位方法可分为产品特征定位、物质利益定位、情感利益定位、个性定位以及价值观定位共五个层次。     

能源安全体系建构的理论与实践

在我国能源安全面临的一系列重大问题中，能源领域的政策规划薄弱，法律保障制度建设与管理体制改革滞后，能源供应与能源安全保障体系缺乏相关政策、法律和制度的保障。只有真正做到政策、法律和管理体制“三位一体”，才能确保国家能源安全。本文从能源安全体系建构的理论和实践出发，借鉴西方能源安全战略实践，从政策、法律和管理体制等角度，对我国能源安全体系的内在机制建构进行分析，旨在为我国与中东能源合作提供借鉴与参考。