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201.
In high-dimensional linear regression, the dimension of variables is always greater than the sample size. In this situation, the traditional variance estimation technique based on ordinary least squares constantly exhibits a high bias even under sparsity assumption. One of the major reasons is the high spurious correlation between unobserved realized noise and several predictors. To alleviate this problem, a refitted cross-validation (RCV) method has been proposed in the literature. However, for a complicated model, the RCV exhibits a lower probability that the selected model includes the true model in case of finite samples. This phenomenon may easily result in a large bias of variance estimation. Thus, a model selection method based on the ranks of the frequency of occurrences in six votes from a blocked 3×2 cross-validation is proposed in this study. The proposed method has a considerably larger probability of including the true model in practice than the RCV method. The variance estimation obtained using the model selected by the proposed method also shows a lower bias and a smaller variance. Furthermore, theoretical analysis proves the asymptotic normality property of the proposed variance estimation.  相似文献   
202.
This study examined how changes in at‐home parents' mental health and parenting practices related to changes in their children's adjustment throughout the course of a service members' military deployment. Participants included at‐home parents from 114 National Guard families who were interviewed at four different occasions across the deployment cycle. The results revealed changes across the deployment cycle among the following three indicators: parental warmth, depressive symptoms, and children's externalizing behaviors. Changes in parental warmth were associated with changes in children's adjustment. Overall, these findings indicate that during parental separation, at‐home parents' responses to children have important implications for children's adjustment.  相似文献   
203.
Deception, in its many forms, is present in families and relationships across the globe. The impact of the presence and discovery of family secrets or deceptive acts on the individual, the family unit, and the therapeutic process, particularly in the field of marriage and family therapy, has not been thoroughly studied or discussed. Further, deceptive acts during the therapeutic process may have implications for effective treatment planning. This article defines the various forms of deception and its systemic effects on relationships and on the therapeutic process. Possible interventions to address deception in a family therapeutic setting are proposed.  相似文献   
204.
陈婷婷 《西北人口》2010,31(1):100-104
根据2006年全国综合调查(CGSS2006)的数据,本文探讨了夫妻权利运行的三个要素:权力基础(教育差、年收入差);权利过程(互诉烦恼、对钱不同意见频率);权利结果(家务差、家庭事务决定权)对婚姻满意度的具体影响。多元回归分析表明:权利过程是影响婚姻满意度最重要的环节,其中配偶向被访者诉说烦恼和对钱不同意见频率都有显著影响:教育差虽也有一定的负向显著度,但其影响程度较小;夫妻年收入差、家务差和家庭事务决定权并无显著性。  相似文献   
205.
We derive a simplified version of the model of Fudenberg and Levine, 2006, Fudenberg and Levine, 2011 and show how this approximate model is useful in explaining choice under risk. We show that in the simple case of three outcomes, the model can generate indifference curves that “fan out” in the Marschak–Machina triangle, and thus can explain the well-known Allais and common ratio paradoxes that models such as prospect theory and regret theory are designed to capture. At the same time, our model is consistent with modern macroeconomic theory and evidence and generates predictions across a much wider set of domains than these models.  相似文献   
206.
ABSTRACT

The article analyses narratives that favoured or opposed European integration in three referendum debates held during the constitutional process of the 2000s: in France and the Netherlands in 2005 (Constitutional Treaty) as well as the first vote in Ireland on the Lisbon Treaty in 2008. In all debates examined, speakers used similar narratives of European integration. While most narrative patterns have transnational character, however, they are also remarkably country-specific. They depend on the specific cultural context and the social positions of the speakers articulating them.  相似文献   
207.
ABSTRACT

A recent prevalence of high visibility catastrophic events has garnered increased attention to process safety issues. While the use of Behavior-Based Safety interventions demonstrate a reduction in workplace injuries by targeting employee behavior, we believe that process safety requires a greater focus on the behavior of leaders (e.g., creating and executing strategy). One effective method to begin targeting leader behavior for the improvement of process safety is to teach leaders about the principles of behavior, including ways by which the science may be applied within their own organizational models.  相似文献   
208.
In this paper, multiple criteria sorting methods based on data envelopment analysis (DEA) are developed to evaluate research and development (R&D) projects. The weight intervals of the criteria are obtained from Interval Analytic Hierarchy Process and employed as the assurance region constraints of models. Based on data envelopment analysis, two threshold estimation models, and five assignment models are developed for sorting. In addition to sorting, these models also provide ranking of the projects. The developed approach and the well-known sorting method UTADIS are applied to a real case study to analyze the R&D projects proposed to a grant program executed by a government funding agency in 2009. A five level R&D project selection criteria hierarchy and an assisting point allocation guide are defined to measure and quantify the performance of the projects. In the case study, the developed methods are observed to be more stable than UTADIS.  相似文献   
209.
商业银行风险管理研究中“违规活动—操作风险—信用风险”风险链条尚未得到足够重视. 巴塞尔委员会全面风险管理框架下的众多风险是分层次的,最底层是合规与操作风险,合规与操作风险做到位能极大降低其他风险发生的概率. 以往由于缺少数据支撑,信用风险的合规与操作风险动因无法建立,本文基于“流程—节点—风险点—控制措施—违规事件”关联模型,建立了合规与操作风险的动因库和损失数据库,并在理论上对风险链条上的风险传递关系进行初步探索. 首先基于流程对合规与操作风险动因进行解析,寻找深层次的人员违规和操作风险动因; 其次,探讨了金融机构如何通过业务流程再造改善合规与操作风险管理; 最后是基于流程的操作风险量化建模. 基于实践,总结提炼了“三位一体”的金融机构合规与操作风险管理模式,包含理论基础、信息系统和保障机制,该模式在诸多金融机构中得到运用,并取得显著成效.  相似文献   
210.
Traditional bioavailability studies assess average bioequivalence (ABE) between the test (T) and reference (R) products under the crossover design with TR and RT sequences. With highly variable (HV) drugs whose intrasubject coefficient of variation in pharmacokinetic measures is 30% or greater, assertion of ABE becomes difficult due to the large sample sizes needed to achieve adequate power. In 2011, the FDA adopted a more relaxed, yet complex, ABE criterion and supplied a procedure to assess this criterion exclusively under TRR‐RTR‐RRT and TRTR‐RTRT designs. However, designs with more than 2 periods are not always feasible. This present work investigates how to evaluate HV drugs under TR‐RT designs. A mixed model with heterogeneous residual variances is used to fit data from TR‐RT designs. Under the assumption of zero subject‐by‐formulation interaction, this basic model is comparable to the FDA‐recommended model for TRR‐RTR‐RRT and TRTR‐RTRT designs, suggesting the conceptual plausibility of our approach. To overcome the distributional dependency among summary statistics of model parameters, we develop statistical tests via the generalized pivotal quantity (GPQ). A real‐world data example is given to illustrate the utility of the resulting procedures. Our simulation study identifies a GPQ‐based testing procedure that evaluates HV drugs under practical TR‐RT designs with desirable type I error rate and reasonable power. In comparison to the FDA's approach, this GPQ‐based procedure gives similar performance when the product's intersubject standard deviation is low (≤0.4) and is most useful when practical considerations restrict the crossover design to 2 periods.  相似文献   
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