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101.
It is known that the normal approximation is applicable for sums of non negative random variables, W, with the commonly employed couplings. In this work, we use the Stein’s method to obtain a general theorem of non uniform exponential bound on normal approximation base on monotone size bias couplings of W. Applications of the main result to give the bound on normal approximation for binomial random variable, the number of bulbs on at the terminal time in the lightbulb process, and the number of m runs are also provided.  相似文献   
102.
文章将房价对企业创新水平的影响归结为"成本效应"及"投资效应"两种影响机制,并分析了房地产价格、房产性投资行为、房产性投资的深化以及企业技术创新产出之间的关系。文章的创新之处在于,将创新要素投入和创新管理水平作为中介变量,从理论和实证两方面检验房价和创新产出的关系。基于提出的理论观点利用A股上市公司数据,对研究假设进行了实证研究,得到如下结论:房价对企业技术创新水平的影响机制至少是通过"成本效应"与"投资效应"两条渠道实现的;房价对企业技术创新水平的"成本效应"是通过技术创新投入作为中介对技术创新成果产生影响;房价对企业技术创新水平的"投资效应"是通过技术创新管理水平作为中介对技术创新成果产生影响;未能证实房产性投资会挤压上市公司技术创新投入。文章的研究结论具有以下重要政策启示意义:应当重视房地产价格对企业技术创新产出的"成本效应"。在新旧动能转换的背景下,创新人才的稀缺性提高了其在劳动力市场的议价能力,作为生活必需品的房屋价格上涨,会导致创新人才的劳动力价格随之上涨,这势必加大企业技术创新投入的负担,影响企业的转型升级和长期发展质量;A股企业的房地产投资并未挤压技术创新投入,但降低了企业创新的效率。在政策上,应当制定相关技术创新效率的考察指标,促进骨干型企业重视其创新效率的提升。  相似文献   
103.
The ‘mixed’ group, officially recognised in the 2001 Census, is one of the most rapidly growing ethnic groups in Britain. Although ‘mixed’ categorisation was added to ethnic coding in NHS datasets, our knowledge of health patterns for this population is meagre. Data quality problems remain a key obstacle, including poor reproducibility of the data and constraints on reporting due to sparse data bias. The consequent minimal and indicative evidence base has focused mainly on risky health behaviours, mental health and generic measures of self-rated health, as it has in the U.S.A. and Canada. There is negligible information on the main underlying causes of death, such as neoplasms, heart disease and stroke. Consideration should be given to pooling data across multiple years of health and general purpose surveys to enable reporting for the four ‘mixed’ categories and adjustment for mediating factors and relevant confounders, such as measures of socio-economic status.  相似文献   
104.
Survival bias is a long recognized problem in case–control studies, and many varieties of bias can come under this umbrella term. We focus on one of them, termed Neyman's bias or ‘prevalence–incidence bias’. It occurs in case–control studies when exposure affects both disease and disease-induced mortality, and we give a formula for the observed, biased odds ratio under such conditions. We compare our result with previous investigations into this phenomenon and consider models under which this bias may or may not be important. Finally, we propose three hypothesis tests to identify when Neyman's bias may be present in case–control studies. We apply these tests to three data sets, one of stroke mortality, another of brain tumors, and the last of atrial fibrillation, and find some evidence of Neyman's bias in the former two cases, but not the last case.  相似文献   
105.
The goal of this study was to examine child and parent predictors of children's hostile attribution bias (HAB) with a particular focus on exploring the associations between parents’ early attribution of child misbehavior and children's HAB in the transition to school age. Participants were 241 children (118 girls) of middle‐income families who were at risk for school‐age conduct problems. Multi‐method, multi‐informant data were collected on maternal attributions of child misbehavior, parental use of corporal punishment, and child attributes (i.e., verbal IQ, effortful control, theory of mind, and emotional understanding) at 3 years, and child HAB in ambiguous situations at 6 years. Results indicated that mothers’ internal explanations for children's misconduct may either reduce or increase children's later HAB depending on the specific content of attributions, such that mothers’ belief that children misbehave because of their internal state (i.e., emotional state or temperament) was associated with lower levels of child HAB, whereas attributing power‐based motives (i.e., manipulative, controlling intentions) in children was associated with higher levels of HAB. The findings are discussed with respect to appreciating the complexity of parents’ explanations for children's behavior, and considering parental cognition as a potential target for early identification and prevention of child HAB and related problems.  相似文献   
106.
In this article, we consider the problem of estimation of mode using two-phase sampling. Ratio- and difference-type estimators in two-phase sampling are proposed. The asymptotic properties of the proposed estimators are studied analytically as well as empirically for different situations for the given cost of surveys. The use of two-phase sampling has been found to be cost saving design while estimating mode by making a proper use of auxiliary information.  相似文献   
107.
This paper addresses the problem of estimating a general parameter using information on an auxiliary variable X. We have suggested a class of exponential-type ratio estimators for the parameter and its properties are studied. It is identified that the estimators due to Upadhyaya et al. [Journal of Statistical Theory and Practice (2011), 5(2), 285–302] and Yadav and Kadilar [Revista Columbiana de Estadistica, (2013), 36(1), 145–152] are members of the proposed estimator. We have also shown that the suggested estimator is more efficient than the estimators of Upadhyaya et al. (2011 Upadhyaya, L.N., Singh, H.P., Chatterjee, S., Yadav, R. (2011). Improved ratio and product exponential type estimators. J. Stat. Theo. Pract. 5 (2): 285302.[Taylor &; Francis Online] [Google Scholar]) and Yadav and Kadilar (2013 Yadav, S.K., Kadilar, C. (2013). Improved exponential type ratio estimator of population variance. Revis. Colum. de Estadist. 36(1): 145152. [Google Scholar]). Numerical illustration is provided in support of the present study.  相似文献   
108.
Scholars agree that we live in a society in which the lion’s share of human needs is supplied by formal organizations. This article deals with how society reached this situation and the challenges embedded in it. We will postulate that there are three basic narratives of human services, which we have named the progress, the social disintegration, and the power narrative. The narratives will be demonstrated through examples from the field of juvenile and adolescent mental health services. We claim that meaningful professional training in human services must expose students to the interpretations, insights, and possible directions for practice in light of each of the narratives.  相似文献   
109.
By integrating cognitive diversity into debiasing literature, this paper contributes towards opening the black box of executive judgment. Based on information processing theory we investigate the role of cognitive diversity in strategic decision making. We apply a vignette-based experimental research design to examine the effect of cognitive diversity in teams on decision maker's illusion of control. The results of these experiments provide evidence for a positive influence of high cognitive diversity for debiasing judgment while similarly indicating no such effect for groups with low cognitive diversity. These findings suggest that group composition aspects can play an important role for improving judgment in decision making teams and open promising new avenues for studying debiasing in behavioral strategy research.  相似文献   
110.
李晓东  刘义军  李秀芳 《创新》2011,5(2):105-108,128
在研究职业教育城乡一体化的过程中,课题组研究探讨出一套根据一个地区或一个职业院校的教育资源合理确定这一地区或者这一学校的招生规模,达到充分利用教育资源,获得最好的教育效益和经济效益的各种定量方法,从而为教育管理部门和职业院校运用数学和经济学理论合理确定招生规模提供参考。  相似文献   
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