Bayesian Variable Selection Under Collinearity

In this article, we highlight some interesting facts about Bayesian variable selection methods for linear regression models in settings where the design matrix exhibits strong collinearity. We first demonstrate via real data analysis and simulation studies that summaries of the posterior distribution based on marginal and joint distributions may give conflicting results for assessing the importance of strongly correlated covariates. The natural question is which one should be used in practice. The simulation studies suggest that posterior inclusion probabilities and Bayes factors that evaluate the importance of correlated covariates jointly are more appropriate, and some priors may be more adversely affected in such a setting. To obtain a better understanding behind the phenomenon, we study some toy examples with Zellner’s g-prior. The results show that strong collinearity may lead to a multimodal posterior distribution over models, in which joint summaries are more appropriate than marginal summaries. Thus, we recommend a routine examination of the correlation matrix and calculation of the joint inclusion probabilities for correlated covariates, in addition to marginal inclusion probabilities, for assessing the importance of covariates in Bayesian variable selection.     

Approximating moments of continuous functions of random variables using Bernstein polynomials

Bernstein polynomials have many interesting properties. In statistics, they were mainly used to estimate density functions and regression relationships. The main objective of this paper is to promote further use of Bernstein polynomials in statistics. This includes (1) providing a high-level approximation of the moments of a continuous function $g\left(X\right)$ of a random variable $X$, and (2) proving Jensen’s inequality concerning a convex function without requiring second differentiability of the function. The approximation in (1) is demonstrated to be quite superior to the delta method, which is used to approximate the variance of $g\left(X\right)$ with the added assumption of differentiability of the function. Two numerical examples are given to illustrate the application of the proposed methodology in (1).     

老人自死习俗:尧舜禹禅让的真相

依据爱德华·泰勒的万物有灵观、弗雷泽的原始巫术思维原理、范热内普的过渡礼仪等人类学经典理论,从尧舜禅让中的舜囚尧,以及典籍中的类比性描述,对《尚书》中年龄数字的剖析,去掉神话历史化、历史道德化的迷雾,尧舜禹禅让的真相是老人自死习俗,周期三年。商末周初,随着观念和习俗的演变,老人生命的终结,逐渐由自死的形式过渡到自然死亡的形式,该习俗已经在国家层面不复存在,并分别演化成"大夫七十而致事"的官礼、"三年之丧"的丧礼。老人自死是那个时代敬老、孝道的重大仪式。     

产业转型、公共支持与农民工就业转变研究

产业转型和政府公共支持是影响农民工就业转变的两个重要因素。从产业转型对农民工就业转变影响、公共支持对农民工就业转变影响、产业转型与公共支持二者间的关系等方面对我国产业转型、公共支持与农民工就业结构文献进行了归纳和评述。在评述的基础上,还对促进农民工实现就业转变进行了深入分析。     

透过情态隐喻看奥巴马的演说词

情态隐喻是政治人士配置情态意义、对情态责任进行编码的常用手段,用以体现话语中复杂的语义内涵,与听众建立人际关系并对其进行引导劝说,最终实现自己的政治目的。     

中重度智障儿童语言康复——从事语言康复的特教教师的经验与困境

通过深度访谈两名从事中重度智障儿童语言康复的特教教师,了解特教教师开展智障儿童语言康复的原则、内容、策略、效果与存在的困难.资料的整理、分析显示,特教教师教育与康复结合,以语言为主、认知和精细动作辅助、以语言理解为重点对智障儿童进行语言康复;更多使用与教育相关的策略,有限地使用口部运动治疗法.特教教师从事语言康复面临专业学习不够、缺乏有经验的指导者和现有语言康复策略很难运用于智障儿童等困境.     

西方生态伦理学的自然地位之争与反思

当代的生态危机在西方伦理学界引发了非人类中心主义对人类中心主义生态观的挑战。争论双方围绕道德主体的范围和自然的道德地位展开了激烈争辩。人类中心主义墨守传统伦理观念,认为道德主体只局限于人。非人类中心主义认为道德主体还应当包括自然,它试图通过强调种际平等,把道德关怀范围扩大至非人类存在物,以解决人类面临的环境危机。通过分析、比较生态伦理学各派的主张,可以对人与自然关系有清醒认识:首先,人类要尊重非人类生命的权利;其次,应恰当处理生态系统中整体与个体的关系;最后,人类还必须对自身的认识偏见时刻保持警醒。     

现代技术道德化初探

现代技术给社会带来了诸多道德问题,且现代技术本身也已经成为一个道德问题。技术“价值中立”观点的直接后果就是造成了技术与道德的两分状态,因此有技术“道德中立”的观点。通过考察技术的本质可知,技术并非完全是一种单纯的手段和工具,技术负载了价值,具有自身的意向结构,正是技术的意向结构决定了技术非“道德中立”。技术应该也必须是一个道德主体,技术道德应该包含义务的道德和愿望的道德①。     

西部地区幼儿教师“国培”满意度与影响因素分析——以重庆市某国培班为例

以重庆市部分参与西部地区幼儿教师脱产置换学员为调查对象,分别调查了学员对培训课程实现自己专业理念与师德、专业知识、专业能力发展的满意度。结果发现各方对“幼儿教师国培”项目目的的理解、承办“国培”单位的管理能力和参与培训幼儿教师的主观态度是影响幼儿教师国培项目满意度的主要影响因素。     

论《神谕女士》中的文体戏仿与女性主体意识

《神谕女士》是加拿大当代作家阿特伍德的代表作品之一,这部小说在文体上戏仿哥特小说,同时体现出对女性主体意识复杂性的思考。女主人公琼成长经历曲折,以写作哥特小说来寄托梦想,哥特小说文体在作品中形成了书中之书的叙事模式。在琼所呈现出的一系列多形态的、不同的自我形象中,可以看出阿特伍德在写作中对多元的、复数的主体的解放。由此,《神谕女士》显现出明显的后现代艺术特征。