法经济学视野下的情势变更

情势变更原则作为一种分配意外风险的规则,可以节约与分配风险相关的交易成本。事实上,无论是理论基础、法律效果还是适用条件,情势变更规则无不具有令人信服的经济学逻辑,始终以提高资源配置效率为中心目标。     

Semantic Analysis of the Theoretical Foundations of Biology

生物学理论作为科学哲学研究中的一个另类一直受到关注。它与传统科学模式间的差异是造成这种现象的原因之一。解读这种差异的根源,需要对生物学的理论基础以及理论结构给予充分的关注。生物学特有理论结构所表现出的多元语境与语义结构的复杂性,决定了对生物学理论基础的研究应当重视语义分析的方法,尤其是对理论本身进行语义分解并研究其中的语义关联问题,从而解读生物学模式作为一种不同于理化科学的特殊科学解释观的合理性。     

论辞格理论与辞格发展之间的互动

古代修辞理论与辞格发展之间存在着复杂的互动关系。本文通过个案分析,证实了三点:其一,辞格的发展、演变本质上依赖于语言、文体本身提供的可能性,辞格理论的影响只是在发展方向上的诱导,并且这种诱导并不是总能成功;其二,这种诱导以理论被辞格使用者认同为前提,而特定文化背景或文学思潮可增强这种认同感,从而强化诱导;其三,当辞格使用者面对关于这一辞格的不同的甚至对立的理论主张时,他们会作出折中或取舍;而理论创造者面对辞格的发展变化,也有可能作出新的概括或补充。     

对创新高校思想政治理论课实践环节的思考

思想政治理论课实践教学环节是理论课教学体系的重要部分,是提升教学效果的有效途径之一。目前,实践教学存在着思想认识上有偏差、缺乏规范有效的组织管理、缺少资金和基地保障、缺乏科学的考核和评价体系等诸多问题,需要通过转变观念、建立和完善组织管理机制、设立专项经费和实践基地、建立健全实践教学评价体系等途径,使理论课实践教学更具有可操作性和实效性。     

A hierarchical model for extreme wind speeds

Summary.  A typical extreme value analysis is often carried out on the basis of simplistic inferential procedures, though the data being analysed may be structurally complex. Here we develop a hierarchical model for hourly gust maximum wind speed data, which attempts to identify site and seasonal effects for the marginal densities of hourly maxima, as well as for the serial dependence at each location. A Gaussian model for the random effects exploits the meteorological structure in the data, enabling increased precision for inferences at individual sites and in individual seasons. The Bayesian framework that is adopted is also exploited to obtain predictive return level estimates at each site, which incorporate uncertainty due to model estimation, as well as the randomness that is inherent in the processes that are involved.     

A BAYESIAN INTERPRETATION OF MULTIPLE POINT ESTIMATES

Consider a large number of econometric investigations using different estimation techniques and/or different subsets of all available data to estimate a fixed set of parameters. The resulting empirical distribution of point estimates can be shown - under suitable conditions - to coincide with a Bayesian posterior measure on the parameter space induced by a minimum information procedure. This Bayesian interpretation makes it easier to combine the results of various empirical exercises for statistical decision making. The collection of estimators may be generated by one investigator to ensure the satisfaction of our conditions, or they may be collected from published works, where behavioral assumptions need to be made regarding the dependence structure of econometric studies.     

静电电子回旋脉塞的单粒子理论

本文用单粒子理论研究了静电电子回旋脉塞。通过对静电电子回旋脉塞中的电子运动的分析,导出了电子与波互作用的非线性摆方程。文中用二阶扰动方法求解非线性摆方程,得到了TE_(mn)和TM_(mn)两种工作模式的静电电子回旋脉塞不稳定性线性增益公式,进一步证实了静电电子回旋脉塞不稳定性是存在的。     

Copula-based regression models: A survey

In this review paper we collect several results about copula-based models, especially concerning regression models, by focusing on some insurance applications.     

A new estimation method for Weibull-type tails based on the mean excess function

Studying the right tail of a distribution, one can classify the distributions into three classes based on the extreme value index γ$\gamma$. The class γ>0$\gamma >0$ corresponds to Pareto-type or heavy tailed distributions, while γ<0$\gamma <0$ indicates that the underlying distribution has a finite endpoint. The Weibull-type distributions form an important subgroup within the Gumbel class with γ=0$\gamma =0$. The tail behaviour can then be specified using the Weibull tail index. Classical estimators of this index show severe bias. In this paper we present a new estimation approach based on the mean excess function, which exhibits improved bias and mean squared error. The asserted properties are supported by simulation experiments and asymptotic results. Illustrations with real life data sets are provided.     

基于核和灰度的双重异构数据序列预测建模方法研究

通过建立灰色异构数据"核"序列的DGM(1,1)模型,实现双重异构数据"核"的预测;以"核"为基础、以双重异构数据序列中较大的区间灰数信息域作为预测结果的信息域,构建基于区间灰数与实数的双重异构数据序列灰色预测模型,有效地将灰色预测模型建模对象从"同质数据"拓展至"双重异构数据"。研究成果对丰富灰色预测模型理论体系具有积极意义。