基于DRSA-T0PSIS法的我国核电上市公司竞争力评价

竞争力是公司综合实力的一个体现,文章对竞争力的评价构建了评价指标体系,以我国核电上市公司为例,运用优势粗糙集将上市公司分类,并运用改进T0PSIS法对其中一类进行排名,以达到简化的作用,而提取出的规则也为今后的竞争力评价提供了参考。     

First difference transformation in panel VAR models: Robustness,estimation, and inference

This article considers estimation of Panel Vector Autoregressive Models of order 1 (PVAR(1)) with focus on fixed T consistent estimation methods in First Differences (FD) with additional strictly exogenous regressors. Additional results for the Panel FD ordinary least squares (OLS) estimator and the FDLS type estimator of Han and Phillips (2010 Han, C., Phillips, P. C. B. (2010). Gmm estimation for dynamic panels with fixed effects and strong instruments at unity. Econometric Theory 26:119–151.[Crossref], [Web of Science ®] , [Google Scholar]) are provided. Furthermore, we simplify the analysis of Binder et al. (2005 Binder, M., Hsiao, C., Pesaran, M. H. (2005). Estimation and inference in short panel vector autoregressions with unit root and cointegration. Econometric Theory 21:795–837.[Crossref], [Web of Science ®] , [Google Scholar]) by providing additional analytical results and extend the original model by taking into account possible cross-sectional heteroscedasticity and presence of strictly exogenous regressors. We show that in the three wave panel the log-likelihood function of the unrestricted Transformed Maximum Likelihood (TML) estimator might violate the global identification assumption. The finite-sample performance of the analyzed methods is investigated in a Monte Carlo study.     

艾略特诗歌与中西诗学传统

艾略特无可比拟的“对当代诗歌作出的卓越贡献和所起的先锋作用”是以其诗作中所蕴涵的中西诗学传统为根基的。西方文学的叙事传统和中国诗歌的简约风格珠联璧合,使其诗作既具有了深厚的历史积淀,又具有了鲜明的时代特征,从而产生了深远的影响力。     

西方文学传统与中国诗学因子的结合与融通——艾略特《荒原》等诗歌艺术性探析

艾略特“对当代诗歌作出的卓越贡献和所起的先锋作用”是无人比拟的。他之所以能够取得这种杰出的成就与其自觉接受西方传统文化的影响和不自觉地吸收中国诗学因素是分不开的。可以说,其诗作与批评理论的不朽也正在于将二者进行了巧妙的融会贯通。     

Type-I-error rate inflation in mixed models for repeated measures caused by ambiguous or incomplete model specifications

Pre-specification of the primary analysis model is a pre-requisite to control the family-wise type-I-error rate (T1E) at the intended level in confirmatory clinical trials. However, mixed models for repeated measures (MMRM) have been shown to be poorly specified in study protocols. The magnitude of a resulting T1E rate inflation is still unknown. This investigation aims to quantify the magnitude of the T1E rate inflation depending on the type and number of unspecified model items as well as different trial characteristics. We simulated a randomized, double-blind, parallel group, phase III clinical trial under the assumption that there is no treatment effect at any time point. The simulated data was analysed using different clusters, each including several MMRMs that are compatible with the imprecise pre-specification of the MMRM. T1E rates for each cluster were estimated. A significant T1E rate inflation could be shown for ambiguous model specifications with a maximum T1E rate of 7.6% [7.1%; 8.1%]. The results show that the magnitude of the T1E rate inflation depends on the type and number of unspecified model items as well as the sample size and allocation ratio. The imprecise specification of nuisance parameters may not lead to a significant T1E rate inflation. However, the results of this simulation study rather underestimate the true T1E rate inflation. In conclusion, imprecise MMRM specifications may lead to a substantial inflation of the T1E rate and can damage the ability to generate confirmatory evidence in pivotal clinical trials.     

新发现颜真卿撰《康阿义屈达干墓志》释证

新发现的颜真卿撰《康阿义屈达干墓志》是一方唐代突厥世族的粟特人墓志。康阿义屈达干是安史之乱前后的重要人物，他的一生关联着唐代两个最大的政治动乱，对唐王朝而言，他是外族忠臣的代表。《康阿义屈达干墓志》记述的康氏的名字和族源，涉及突厥内乱与康氏归朝、康氏与安史之乱、康氏与代宗幸陕等重大历史事件与民族问题。颜真卿为康氏撰写墓志与康氏之子康没野波在平原之战中保全颜真卿有关。