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61.
In this paper, we consider estimation of the mean squared prediction error (MSPE) of the best linear predictor of (possibly) nonlinear functions of finitely many future observations in a stationary time series. We develop a resampling methodology for estimating the MSPE when the unknown parameters in the best linear predictor are estimated. Further, we propose a bias corrected MSPE estimator based on the bootstrap and establish its second order accuracy. Finite sample properties of the method are investigated through a simulation study.  相似文献   
62.
Abstract. We consider model‐based prediction of a finite population total when a monotone transformation of the survey variable makes it appropriate to assume additive, homoscedastic errors. As the transformation to achieve this does not necessarily simultaneously produce an easily parameterized mean function, we assume only that the mean is a smooth function of the auxiliary variable and estimate it non‐parametrically. The back transformation of predictions obtained on the transformed scale introduces bias which we remove using smearing. We obtain an asymptotic expansion for the prediction error which shows that prediction bias is asymptotically negligible and the prediction mean‐squared error (MSE) using a non‐parametric model remains in the same order as when a parametric model is adopted. The expansion also shows the effect of smearing on the prediction MSE and can be used to compute the asymptotic prediction MSE. We propose a model‐based bootstrap estimate of the prediction MSE. The predictor produces competitive results in terms of bias and prediction MSE in a simulation study, and performs well on a population constructed from an Australian farm survey.  相似文献   
63.
This paper considers alternative estimators of the intercept parameter of the linear regression model with normal error when uncertain non-sample prior information about the value of the slope parameter is available. The maximum likelihood, restricted, preliminary test and shrinkage estimators are considered. Based on their quadratic biases and mean square errors the relative performances of the estimators are investigated. Both analytical and graphical comparisons are explored. None of the estimators is found to be uniformly dominating the others. However, if the non-sample prior information regarding the value of the slope is not too far from its true value, the shrinkage estimator of the intercept parameter dominates the rest of the estimators.  相似文献   
64.
虚拟空间交织是人们常用的思维与认知方式之一。本文通过对交织及其原则的介绍,描述了虚拟空间交织的运作,指出虚拟空间交织构建中主观取向的原则应为最佳关联。  相似文献   
65.
运用超额收益法对深圳和上海证券市场的股利政策市场效应进行实证研究,探析不同类型股利的市场效应及投资者行为。结果表明,中国证券投资者在投资决策过程由于受心理因素的影响,对于不同类型的股利政策做出了不同的市场反应,并表现出一定的股利偏好行为,即证券投资者对现金股利政策,尤其稳定的现金股利政策表现出明显的喜好行为,而对于不分配股利政策却表现出了漠视效应行为。  相似文献   
66.
文章分析了通用性指标偏好产生的原因、影响和解决途径,并通过实验研究,考察了中国实验者在平衡计分卡应用中是否也存在通用性指标偏好,以及集体决策方式对通用性偏好程度的影响。决策者组成的多元化,是集体决策发挥作用的重要因素,这一结论对于部门平衡计分卡在现实中的应用和企业绩效评价实践具有启示作用。  相似文献   
67.
学前儿童性别教育的有关研究表明,社会上还存在着根深蒂固的性别歧视和性别偏见,身处特定环境中的学前教育教师以及图画书、教学媒体等仍然带有较强的性别歧视和性别偏见等性别刻板印记。为此,国家需要在学前儿童性别教育研究的基础上重视学前教育阶段的性别平等教育,制定相关的政策,建立性别教育的终身教育体系,构建教师性别平等教育的培训网络平台,以现代性别教育理念为指导,基于对儿童生理差异的尊重,设计出适合学前儿童身心发展特点的性别教育课程,全面有效地实施性别平等教育。  相似文献   
68.
Abstract

The present study confirms the influential role of a positively and a negatively correlated auxiliary variables in enhancing the precision of estimates of current population mean in two occasion rotation (successive) sampling. Exponential-type estimators of current population mean have been proposed for three different situations: (i) the information on a positively correlated auxiliary variable is readily available on both occasions (ii) the information on a negatively correlated auxiliary variable is readily available on both occasions and (iii) the information on both positively and negatively correlated auxiliary variables are readily available on both the occasions. The characteristics of the proposed estimators have been explored and their efficacious performances are compared with the natural and recent contemporary estimators. Optimum replacement strategies of the proposed estimation procedures have been formulated. Simulation and empirical studies are carried out to justify the proposition of the proposed estimators and appropriate recommendations have been put forward to the survey practitioners.  相似文献   
69.
In regenerative simulation, one frequently requires an estimate or a confidence interval for the ratio of the means of the two components of a certain bivariate random quantity. Estimation of this ratio has been studied by many authors and most recently by Asmussen and Rydén(2010 Asmussen, S., Rydén, T. (2010). A note on skewness in regenerative simulation. Communications in Statistics—Simulation and Computation 40: 4557.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]). Here, we propose an estimate that performs better than the best of the known estimates. Our estimate is also lot simpler than the best known estimate.  相似文献   
70.
More than 500 Aboriginal women have gone missing or been murdered in Canada since the 1980s yet press attention to this violence is relatively minimal. This paper compares local press coverage of matched cases: three missing/murdered Aboriginal women from Saskatchewan and three missing/murdered White women from Ontario. Quantitative and qualitative content analyses indicate stark disparities in the amount and content of coverage between groups. The Aboriginal women received three and a half times less coverage; their articles were shorter and less likely to appear on the front page. Depictions of the Aboriginal women were also more detached in tone and scant in detail in contrast to the more intimate portraits of the White women. Drawing on feminist media studies and theories of intersectionality, this paper argues that the simultaneous devaluation of Aboriginal womanhood and idealization of middle-class White womanhood contributes to broader systemic inequalities which re/produce racism, sexism, classism, and colonialism. This paper raises concerns about the broader implications of the relative invisibility of missing/murdered Aboriginal women in the press, and their symbolic annihilation from the Canadian social landscape.  相似文献   
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