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281.
Order statistics from trivariate normal and -distributions in terms of generalized skew-normal and skew- distributions 总被引:1,自引:0,他引:1
We consider here a generalization of the skew-normal distribution, GSN(λ1,λ2,ρ), defined through a standard bivariate normal distribution with correlation ρ, which is a special case of the unified multivariate skew-normal distribution studied recently by Arellano-Valle and Azzalini [2006. On the unification of families of skew-normal distributions. Scand. J. Statist. 33, 561–574]. We then present some simple and useful properties of this distribution and also derive its moment generating function in an explicit form. Next, we show that distributions of order statistics from the trivariate normal distribution are mixtures of these generalized skew-normal distributions; thence, using the established properties of the generalized skew-normal distribution, we derive the moment generating functions of order statistics, and also present expressions for means and variances of these order statistics.Next, we introduce a generalized skew-tν distribution, which is a special case of the unified multivariate skew-elliptical distribution presented by Arellano-Valle and Azzalini [2006. On the unification of families of skew-normal distributions. Scand. J. Statist. 33, 561–574] and is in fact a three-parameter generalization of Azzalini and Capitanio's [2003. Distributions generated by perturbation of symmetry with emphasis on a multivariate skew t distribution. J. Roy. Statist. Soc. Ser. B 65, 367–389] univariate skew-tν form. We then use the relationship between the generalized skew-normal and skew-tν distributions to discuss some properties of generalized skew-tν as well as distributions of order statistics from bivariate and trivariate tν distributions. We show that these distributions of order statistics are indeed mixtures of generalized skew-tν distributions, and then use this property to derive explicit expressions for means and variances of these order statistics. 相似文献
282.
In this paper, we consider finite populations and investigate their characterizations by regressions of order statistics under sampling without replacement. We also investigate some asymptotic results when the size of the population goes to infinity. 相似文献
283.
本文在浙江省制造业1454家企业大样本调查问卷的基础上,在微观层面研究了企业创新行为以及影响因素。首先利用统计分析的方法考察了企业创新投入的特征、创新投入的行业分布以及创新投入的产出绩效,并且发现了企业规模与R&;D强度之间呈现倒U型关系,这与安同良等人发现的倾斜V型关系的结论不同。其次运用计量分析的方法在有效控制了企业所处行业的技术水平差异、企业产权结构、政府资金扶持、企业品牌和企业设备技术水平后,研究发现:企业规模与企业创新投入之间也呈现较明显的倒U型关系,并且存在规模“拐点”;企业知识产权战略对企业创新投入具有明显的促进作用;出口贸易对企业创新投入并不显著,但发达国家特别是针对发展中国家设置的技术性贸易壁垒的技术标准化要求对企业创新投入有比较明显的促进作用;而企业集聚对企业的创新投入的影响并不确定。 相似文献
284.
285.
人类已经进入"第五媒体时代".继报纸、广播、电视、互联网之后的第五媒体抑或是手机媒体.具有媒介粘滞、瞬时精准、病毒式营销等无与伦比的传播特性.第五媒体是柄"双刃剑",它在给政府公共关系带来前所未有的挑战的同时,也带来了前所未有的机遇.利用第五媒体开拓政府公共关系的新视野,是一个政治、社会问题,也是一个技术、法律问题. 相似文献
286.
民族地区能源、经济与环境系统协调评价研究 总被引:2,自引:0,他引:2
随着我国民族地区经济的发展,能源和环境对经济的制约越来越强,能源—经济—环境[3E]系统协调矛盾凸显。本文旨在科学发展观的指导下,通过建立民族地区3E系统协调评价体系和评价指标,并结合实证数据,分析研究民族地区3E系统存在的主要问题,提出促进民族地区3E系统协调性发展的建议。 相似文献
287.
Dimitris Boucas 《The British journal of sociology》2017,68(3):556-580
The paper looks into the dynamics of information society policy and its implementation in the Greek context. It argues that information society development is a contested process, influenced by pre‐existing state, economy and society relations. Based on this, it looks into the different aspects of the idiosyncratic path which the evolution of the Greek information society has followed, particularly after 2000. Using Bob Jessop's strategic‐relational approach (SRA) to the state as an analytical framework and drawing on a number of in‐depth interviews with relevant political actors, it provides insights into policy implementation by examining: the public management of information technology projects, how such projects were received in bureaucratic structures and practices, as well as the relationship between the state and the information and communication technology (ICT) sector in public procurement processes. The emphasis is on the period 2000–2008, during which a major operational programme on the information society in Greece was put into effect. The paper also touches upon the post‐2008 experience, suggesting that information society developments might include dynamics operating independently and even in contradiction to the state agenda. 相似文献
288.
Janet McDonald Eileen McKinlay Sally Keeling William Levack 《Kōtuitui : New Zealand Journal of Social Sciences Online》2017,12(2):246-255
Over the last 50 years, increasingly complex care (such as tracheostomy management, dialysis or enteral feeding) has shifted from hospital to home, with a concomitant rise in patient self-management and care given by family members. Recognition of the importance of the contribution of family care to the health system is also growing. This article reports the findings of a New Zealand study which explored the experiences of family carers who manage technical health procedures at home. It then draws attention to some broader issues raised by shifting complex care from professional management in hospital settings to family care at home, namely the ways in which complex home care blurs the boundaries between professional and family care (creating the ambiguous position of the expert carer) and questions of safety and responsibility in family care. We also discuss the implications for policy around family caregiving in New Zealand. Given the potential physical and mental health impacts of caring, it is time for renewed consideration of what family carers should be expected or allowed to manage and how the health system can support them in their important role. 相似文献
289.
夏劲 《重庆邮电大学学报(社会科学版)》2017,29(3):20-22
由中国自然辩证法研究会科技文化专业委员会主办,九江学院马克思主义学院和武汉理工大学政治与行政学院共同承办的“第十三届全国科技文化与社会现代化学术研讨会”于2016年8月23日至24日在江西省九江学院隆重召开,来自全国18个省市的90余位专家、学者出席了会议. 相似文献
290.
Perception of peer rank, or how we perform relative to our peers, can be a powerful motivator. While research exists on the effect of social information on decision making, there is less work on how ranked comparisons with our peers influence our behavior. This paper outlines a field experiment conducted with 3896 households in Castro Valley, California, which uses household mailers with various forms of social information and peer rank messaging to motivate water conservation. The experiment tests the effect of a visible peer rank on water use, and how the competitive framing of rank information influences behavioral response. The results show that households with relatively low or high water use in the pre-treatment period responded differently to how rank information was framed. I find that a neutrally-framed peer rank caused a small “boomerang effect” (i.e., an increase in average water use) for low water use households, but this effect was eliminated by competitive framing. At the same time, a competitively-framed peer rank demotivated high water use households, increasing their average water use over the full period of the experiment. This result is supported by evidence that the competitive frame on rank information increased water use for households who ranked “last” in the peer group – a detrimental “last place effect” from competitively-framed rankings. 相似文献