Accurate computation of single and product moments of order statistics under progressive censoring

An accurate procedure is proposed to calculate approximate moments of progressive order statistics in the context of statistical inference for lifetime models. The study analyses the performance of power series expansion to approximate the moments for location and scale distributions with high precision and smaller deviations with respect to the exact values. A comparative analysis between exact and approximate methods is shown using some tables and figures. The different approximations are applied in two situations. First, we consider the problem of computing the large sample variance–covariance matrix of maximum likelihood estimators. We also use the approximations to obtain progressively censored sampling plans for log-normal distributed data. These problems illustrate that the presented procedure is highly useful to compute the moments with precision for numerous censoring patterns and, in many cases, is the only valid method because the exact calculation may not be applicable.     

A misspecification test for the higher order co-moments of the factor model

The traditional estimation of higher order co-moments of non-normal random variables by the sample analog of the expectation faces a curse of dimensionality, as the number of parameters increases steeply when the dimension increases. Imposing a factor structure on the process solves this problem; however, it leads to the challenging task of selecting an appropriate factor model. This paper contributes by proposing a test that exploits the following feature: when the factor model is correctly specified, the higher order co-moments of the unexplained return variation are sparse. It recommends a general to specific approach for selecting the factor model by choosing the most parsimonious specification for which the sparsity assumption is satisfied. This approach uses a Wald or Gumbel test statistic for testing the joint statistical significance of the co-moments that are zero when the factor model is correctly specified. The asymptotic distribution of the test is derived. An extensive simulation study confirms the good finite sample properties of the approach. This paper illustrates the practical usefulness of factor selection on daily returns of random subsets of S&P 100 constituents.     

Ordering results for series and parallel systems comprising heterogeneous exponentiated Weibull components

In this paper, we discuss the usual stochastic and reversed hazard rate orders between the series and parallel systems from two sets of independent heterogeneous exponentiated Weibull components. We also obtain the results concerning the convex transform orders between parallel systems and obtain necessary and sufficient conditions under which the dispersive and usual stochastic orders, and the right spread and increasing convex orders between the lifetimes of the two systems are equivalent. Finally, in the multiple-outlier exponentiated Weibull models, based on weak majorization and p-larger orders between the vectors of scale and shape parameters, some characterization results for comparing the lifetimes of parallel and series systems are also established, respectively. The results of this paper can be used in practical situations to find various bounds for the important aging characteristics of these systems.     

A new aging concept derived from the increasing convex ordering

In this paper, a comparison between the life distribution of a new unit with that of a used unit in the increasing convex order is made leading to a new class of life distributions which we call “new better than used in convex ordering of second order”. This class includes as subclasses the NBU and the NBUC and is a subclass of the NBUCA class. Preservation properties under convolution, random maxima, mixing and formation of coherent structures are established. Stochastic comparisons of the excess lifetime when the inter-arrival times belong to the NBUC(2) class are developed. Some applications of Poisson shock models and a test of exponentiality against NBUC(2) alternative are presented.     

熵理论与和谐社会

熵理论揭示了任何事物和过程都是有序和无序的辩证统一,人类社会的发展也是有序和无序的辩证统一。构建和谐社会的实质就是克服无序(不和谐)、创建有序(和谐),实现安定有序。这是建设中国特色社会主义的重大任务。     

法律信仰缺失的历史主义与现实主义分析及对策

良法并不代表法治,法治是法律被信仰的神圣化过程与结果。客观而言,我们这一代中国人已基本上实现了法律文本的法治,然而如何将这种立法法治转变为法治秩序是我们必须思考的问题。法律先是一个社会问题,然后才是一个制度问题。因此,中国法律确信之路的探讨必须先是一个历史传统文化的客观讨论与批判,然后才是一个制度的设计问题。     

专业化交易组织成长与区域经济发展--再论农村市场经济发展的"义乌模式"

义乌区域经济发展的动因不是工业化,而是市场化;商人的集体行动与政府的开明决策,使义乌成为全国最大的小商品流通中心;"义乌模式"的优势,在于交易方式的专业化,小商品市场的专业化交易形成了信息规模经济、外部规模经济和范围经济,从而确立了义乌小商品的低成本优势;尔后,市场秩序扩展、专业化交换组织成长与产业集聚发展的良性互动,形成了义乌独特的工业化、城市化路径.     

宪政治理与公民参与

公民参与是宪政秩序下民主价值的体现。公民参与能够在宪政治理中重构政府与公民之间的关系 ,进而实现国家权力和公民权利间的平衡。因此 ,当前应积极探索多种有效途径以促进公民参与的发展。研究这一问题对于推进我国的行政民主化建设有着重大的现实意义     

世界金融秩序变迁研究：基于国际政治经济学视角

现代世界金融秩序,是一个历史的动态过程,主要经历了以阿姆斯特丹为中心的荷兰世界金融秩序、以伦敦为中心的不列颠世界金融秩序、以纽约为中心的美国世界金融秩序。阿姆斯特丹—伦敦—纽约的更迭一直沿着中心化—去中心化—再中心化的路径。世界金融秩序的空间基础在于世界金融中心。世界金融中心崛起的关键在于它们各自的政治经济实力的相对上升、资本的积累和其货币作为世界货币。大规模战争在世界金融权力的转移、世界金融秩序的变迁中具有重大影响,甚至起着关键作用。市场在世界金融秩序和世界金融中心的形成、发展中起着基础性作用,政府干预的作用是有限的,但是政府在世界金融秩序的权力结构和治理结构的地位越来越大。     

论党的三代领导人国际统一战线思想的不同风格

党的三代领导人的国际统战思想既是共产党人集体智慧的结晶,又是对马列主义的创造性发展。他们由于身处不同的国际环境,其国际统战思想具有不同的个人风格:毛泽东侧重于国家安全;邓小平注重国家经济发展;江泽民强调建立一个公正合理的国际新秩序,提升中国在未来世界格局中的地位。