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81.
本文阐述了过程能力指数的发展形式及存在的问题,探索了过程能力指数的优化途径,建立了基于质量损失与过程控制成本之和最小化的过程能力指数模型.  相似文献   
82.
集装箱运输货损责任法律问题研究   总被引:1,自引:0,他引:1  
从对集装箱性质的分析入手 ,通过对与集装箱运输货物责任相关问题的研究及各国实践做法的介绍 ,试图使集装箱运输货损责任的认定清晰化、简单化。同时对现有法律中存在的问题加以说明 ,以使法律能够尽快被完善 ,尽快适应集装箱运输方式快速发展的步伐  相似文献   
83.
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.  相似文献   
84.
Oracle Inequalities for Convex Loss Functions with Nonlinear Targets   总被引:1,自引:1,他引:0  
This article considers penalized empirical loss minimization of convex loss functions with unknown target functions. Using the elastic net penalty, of which the Least Absolute Shrinkage and Selection Operator (Lasso) is a special case, we establish a finite sample oracle inequality which bounds the loss of our estimator from above with high probability. If the unknown target is linear, this inequality also provides an upper bound of the estimation error of the estimated parameter vector. Next, we use the non-asymptotic results to show that the excess loss of our estimator is asymptotically of the same order as that of the oracle. If the target is linear, we give sufficient conditions for consistency of the estimated parameter vector. We briefly discuss how a thresholded version of our estimator can be used to perform consistent variable selection. We give two examples of loss functions covered by our framework.  相似文献   
85.
We estimate two well-known risk measures, the value-at-risk (VAR) and the expected shortfall, conditionally to a functional variable (i.e., a random variable valued in some semi(pseudo)-metric space). We use nonparametric kernel estimation for constructing estimators of these quantities, under general dependence conditions. Theoretical properties are stated whereas practical aspects are illustrated on simulated data: nonlinear functional and GARCH(1,1) models. Some ideas on bandwidth selection using bootstrap are introduced. Finally, an empirical example is given through data of the S&P 500 time series.  相似文献   
86.
This research provides a generalized framework to disaggregate lower-frequency time series and evaluate the disaggregation performance. The proposed framework combines two models in separate stages: a linear regression model to exploit related independent variables in the first stage and a state–space model to disaggregate the residual from the regression in the second stage. For the purpose of providing a set of practical criteria for assessing the disaggregation performance, we measure the information loss that occurs during temporal aggregation while examining what effects take place when aggregating data. To validate the proposed framework, we implement Monte Carlo simulations and provide two empirical studies. Supplementary materials for this article are available online.  相似文献   
87.
88.
We use individual data from a panel of families during the depth of the peso crisis in Mexico to investigate whether the transition of the male household head from employment into unemployment affects the labor force participation of his spouse and children. We find that significant added-worker effects are in operation especially for adult females (wives), but no evidence that the labor force participation, the school attendance, and the likelihood of advancing to the next school grade of teenage males are influenced by the event of unemployment of the household head. The head's unemployment is significantly associated with a higher probability that teenage females do not attend school. However, lower attendance does not appear to impede their advancement to the next grade.
Susan W. ParkerEmail:
  相似文献   
89.
BackgroundRapid changes to how maternity health care is delivered has occurred in many countries across the globe in response to the COVID-19 pandemic. Maternity care provisions have been challenged attempting to balance the needs and safety of pregnant women and their care providers. Women experiencing a pregnancy after loss (PAL) during these times face particularly difficult circumstances.AimIn this paper we highlight the situation in three high income countries (Australia, Ireland and USA) and point to the need to remember the unique and challenging circumstances of these PAL families. We suggest new practices may be deviating from established evidence-based guidelines and outline the potential ramifications of these changes.FindingsRecommendations for health care providers are suggested to bridge the gap between the necessary safety requirements due to the pandemic, the role of the health care provider, and the needs of families experiencing a pregnancy after loss.DiscussionChanges to practices i.e. limiting the number of antenatal appointments and access to a support person may have detrimental effects on both mother, baby, and their family. However, new guidelines in maternity care practices developed to account for the pandemic have not necessarily considered women experiencing pregnancy after loss.ConclusionBereaved mothers and their families experiencing a pregnancy after loss should continue to be supported during the COVID-19 pandemic to limit unintended consequences.  相似文献   
90.
There is growing recognition of the experience of non-death-related loss and grief. One unexplored area of non-death-related loss and grief is associated with older people’s transition from home to residential aged care (RAC). This paper reports findings from a qualitative study that explored the experiences of people living in RAC, carer-relatives of people living in RAC and RAC staff. Using theories of loss and grief, the paper identifies features of the transition to RAC that are associated with unresolved loss and maladaptation to changed circumstances, and the types of support that would mitigate these. Using a series of focus groups with both residents and carer-relatives, as well as staff, the study found that residents and their families need more support to negotiate the multiple, often necessarily hasty decisions and bureaucratic requirements associated with transitioning to RAC, while simultaneously experiencing loss and grief. The types of support that families would welcome from service providers include facilitating shared decision making, valuing family and community carer expertise and providing practical information and assistance to fulfil administrative obligations.  相似文献   
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