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11.
The literature on sequential estimation problems for negative exponential populations has been reviewed here, We attempt to bring in all the published and unpublished materials known to us in a fairly coherent fashion. Both the concepts and theoretical findings are discussed.  相似文献   
12.
Likelihood ratio tests for the homogeneity of k normal means with the alternative restricted by an increasing trend are considered as well as the likelihood ratio tests of the null hypothesis that the means satisfy the trend. While the work is primarily a survey of results concerning the power functions of these tests, the extensions of some results to the case of not necessarily equal sample sizes are presented. For the case of known or unknown population variances, exact expressions are given for the power functions for k=3,4, and approximations are discussed for larger k. The topics of consistency, bias and monotonicity of the power functions are included. Also, Bartholomew's conjectures concerning minimal and maximal powers are investigated, with results of a new numerical study given.  相似文献   
13.
In his articles (1966-1968) concerning statistical inference based on lower and upper probabilities, Dempster refers to the connection between Fisher's fiducial argument and his own ideas of statistical inference. Dempster's main concern however focuses on the “Bayesian” aspects of his theory and not on an elaboration of the relation between Fisher's and his ideas. This article attempts to work out the connection between those two approaches and focuses primarily on the question, whether Dempster's combination rule, his upper and lower probabilty based on sufficient statistics and inference based on sufficient statistics in Fisher's sense are consistent. To be adequate to Fisher's reasoning, we deal with absolutely continuous, one parametric families of distributions.This is certainly not the usual assumption in context with Dempster's theory and implies a normative but straightforward definition concerning the underlying conditional distribution; this definition however is done in Dempster's spirit as can be seen from his articles, (1966, 1968,a,b). Under those assumptions it can be shown that - similar to Lindley's results concerning consistency in fiducial reasoning (1958) - the combination rule, Dempster's procedure based on sufficient statistics and fiducial inference by sufficient statistics agree iff the parametric family under consideration can be transformed to location parameter form.  相似文献   
14.
Nonparametric smoothing, such as kernel or spline estimation, has been examined extensively under the assumption of uncorrelated errors. This paper addresses the effects of potential correlation on consistency and other asymptotic properties in a repeated-measures model, using directly optimized linear smoothers of the replicate means. Unrestricted optimal weights, with respect to squared error loss, are used to confirm a lack of consistency for all linear estimators in an autocorrelated errors model. The results indicate kernel methods that work well for an uncorrelated errors model may not have the ability to perform satisfactorily when correlation is introduced, due to an asymmetry in the optimal weights, which disappears for an uncorrelated errors model. These would include data-driven bandwidth selection methods, adjustments of the bandwidth to accommodate correlation, higher-order kernels, and related bias reduction techniques. The analytic results suggest alternative approaches, not considered here in detail, which have shown merit.  相似文献   
15.
We study the normal variance-mean mixture model from a semiparametric point of view, i.e. we let the mixing distribution belong to a non-parametric family. The main results are consistency of the non-parametric maximum likelihood estimator and construction of an asymptotically normal and efficient estimator for the Euclidian part of the parameter. We study the model according to the theory outlined in the monograph by Bickel et al. (1993) and apply a general result (based on the theory of empirical processes) for semiparametric models from van der Vaart (1996) to prove asymptotic normality and efficiency of the proposed estimator.  相似文献   
16.
P2P系统的应用,使得作品的传播变得更加方便与快捷,也使得对作品的侵权越来越成为可能,为了寻求文化艺术作品的传播与版权人利益保护之间的平衡,从网络技术和法律方法相结合的角度,研究了P2P系统中的著作权侵权问题。认为P2P系统中的著作权侵权应当适用过错责任的归责原则。根据这一原则,只要ICP所提供的内容侵权,就需要承担侵权责任,软件提供商在明知或应知软件侵权的情况下仍然提供服务也应当承担侵权责任,软件经营者则可以适用"通知与删除"规则,在有证据表明有人利用P2P系统侵害著作权的情况下,软件经营者应当停止相应服务,否则就应当承担侵权责任。而对于P2P用户,则可要求其对其共享文件夹中的侵权作品承担侵权责任。  相似文献   
17.
A version of the multiple decsion problem is studied in which the procedure is based only on the current observation and the previous decision. A necessary and sufficient condition for inconsistency of the stepwise maximum likelihood procedure is shown to be the boundedness of the likelihood ratios. In the case of consistency the (typically slow) rate of convergence to zero of the error probabilities is determined.  相似文献   
18.
随着社会化媒体的快速发展,顾客选择日趋多样化,提升顾客品牌心理所有权成为理论和实践共同关注的重要课题。虽然学术界关于品牌心理所有权的概念和维度仍存在些许分歧,但品牌心理所有权对品牌及企业的重要性已得到广泛认可。基于社会心理学原理,以虚拟社区为载体实证分析顾客认知因素、品牌价值观一致性、品牌心理所有权三者之间的内在关系,有助于企业深入了解顾客对品牌心理所有权的影响因素,为企业制定正确的营销战略提供理论与实践指导。  相似文献   
19.
本文分析了公司内部治理结构中委托代理关系中存在的问题,指出这些问题主要是表现在逆向选择和道德风险上,这主要是由于信息不对称引起的,并且指出现存的几种内部控制机制的弊端,提出必须建立充分信息才能从根本上消除这些问题。  相似文献   
20.
运用翻译目的论和翻译接受美学等相关理论探讨了经贸外宣资料的翻译目的和译文读者的阅读需求以及两者之间的关系,提出了指导经贸外宣资料翻译的三条原则:即选择适量的信息,文本功能语用对等和概念术语译名统一,并用具体译例论述这些原则在翻译实践的具体运用。  相似文献   
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