Use of non-normality in structural equation modeling: Application to direction of causation

Structural equation modeling (SEM) typically utilizes first- and second-order moment structures. This limits its applicability since many unidentified models and many equivalent models that researchers would like to distinguish are created. In this paper, we relax this restriction and assume non-normal distributions on exogenous variables. We shall provide a solution to the problems of underidentifiability and equivalence of SEM models by making use of non-normality (higher-order moment structures). The non-normal SEM is applied to finding the possible direction of a path in simple regression models. The method of (generalized) least squares is employed to estimate model parameters. A test statistic for examining a fit of a model is proposed. A simulation result and a real data example are reported to study how the non-normal SEM approach works empirically.     

实验与颠覆：传记中的现代派与后现代

现代派和后现代对传记的真实性原则发起冲击。伍尔芙的《奥兰多传》对传主生平进行变形处理。马尔罗的《反回忆录》打破了叙述的顺序并加上虚构的内容,反映了现代派传记的实验性质。后现代对传记的真实性表示怀疑并颠覆传记的传统标准,奈依关于爱迪生的“反传记”、汤婷婷的《女勇士》、莫里斯的《里根回忆录》和格林布拉特的《尘世威尔》等作品出于不同的价值目标,在传记的外形中加入了更多的虚构和想象。传记要回应这一挑战就应当坚守真实性的原则并承认真实的相对性。     

一个新Hilbert型积分不等式

通过引入权函数的方法,利用Beta函数和带权的Hlder不等式,建立了一个新Hilbert型积分不等式及其等价形式,并证明了其常数因子是最佳值.     

张学良与中东路事件的缘起

关于中东路权益的交涉,是伴随铁路修建开始的,到上世纪20年代初,中俄双方先后签订了《中俄协定》、《奉俄协定》后,交涉中的矛盾并未因此而结束。张学良执掌东北军政后,为争取两协定赋予中方的权益,对苏采取了强硬的交涉手段,导致中东路事件的发生。中东路事件发生后,致使收回中东路权益的目标未能实现。客观分析,张学良收回中东路权益的初衷及强硬立场是正确的,但他对内外局势的错误判断,并接受蒋介石"武力接管"中东路的主张是错误的。从外交史上看,这一教训是深刻的。     

西安事变后东北军的蜕变及原因

西安事变后,东北军由一支较稳定的地方军阀集团迅速蜕变为各自为政的数支军队.这种蜕变主要表现为东北军内部派系纷争的表面化,高级将领的离心和东北军对"三位一体"的背离.东北军的蜕变是由于张学良的被扣、高级将领的裹胁和南京政府的分化,但归根到底则源自其军阀属性.东北军的蜕变瓦解了这支地方实力派,但却有利于国家的统一和整合.     

杜鲁门拒蒋"出兵"缘由初探

朝鲜战争期间,杜鲁门为了避免美苏、美中冲突及其扩大化,防止台湾"陷落"以及盟国分裂,加上不信任蒋介石及其军队的作用,故而拒绝蒋介石"出兵"朝鲜的请求.     

从MPEG-2到H．264的视频格式转换算法

在MPEG-1、MPEG-2、H．263等视频编码方法中，都是采用离散余弦变换（Discrete cosine transform．DCT）编码；而在最新的国际视频编码标准H．264／MPEG4-AVC中，采用了一种新的编码方法——整数变换（Integer transform，IT）．对上述2种方法进行了分析说明，详细推导讨论了一种在变换域中完整地将DCT参数转换为IT参数的方法，对现有方法提出修正，并对采用不同方法编码和解码后的图像质量进行了比较，为从MPEG-1、MPEG-2、H．263等格式的视频直接转换为H．264／MPEG4-AVC格式的视频提供了算法依据．     

Information attainable in some randomly incomplete multivariate response models

In a general parametric setup, a multivariate regression model is considered when responses may be missing at random while the explanatory variables and covariates are completely observed. Asymptotic optimality properties of maximum likelihood estimators for such models are linked to the Fisher information matrix for the parameters. It is shown that the information matrix is well defined for the missing-at-random model and that it plays the same role as in the complete-data linear models. Applications of the methodologic developments in hypothesis-testing problems, without any imputation of missing data, are illustrated. Some simulation results comparing the proposed method with Rubin's multiple imputation method are presented.     

Large‐sample tests of extreme‐value dependence for multivariate copulas

Starting from the characterization of extreme‐value copulas based on max‐stability, large‐sample tests of extreme‐value dependence for multivariate copulas are studied. The two key ingredients of the proposed tests are the empirical copula of the data and a multiplier technique for obtaining approximate p‐values for the derived statistics. The asymptotic validity of the multiplier approach is established, and the finite‐sample performance of a large number of candidate test statistics is studied through extensive Monte Carlo experiments for data sets of dimension two to five. In the bivariate case, the rejection rates of the best versions of the tests are compared with those of the test of Ghoudi et al. (1998) recently revisited by Ben Ghorbal et al. (2009). The proposed procedures are illustrated on bivariate financial data and trivariate geological data. The Canadian Journal of Statistics 39: 703–720; 2011. © 2011 Statistical Society of Canada     

唐君毅对中国艺术精神主体的发掘和发现

唐君毅是标举中国艺术精神的第一人,他着重阐释中国艺术精神的主体层面,认为"游"的精神是西方艺术所缺乏的一种主体精神,进而以中西比较视野加以观照,指出其根源在"感通之德"。他虽未像徐复观一样使中国艺术精神之主体完全呈现,但却有着隐在的表达:虚灵明觉心乃中国艺术精神之主体。唐君毅对中国艺术精神主体的发掘和发现,与徐复观阐释的"中国艺术精神"是有着内在一致性的。这个话题的终极指向,并非艺术,而是精神。