因子模型在风险预算分析中的应用

风险预算在国外正赢得学术界、养老基金和资产管理领域等许多方面的广泛关注,并认为是组合管理的一种创新。国内投资者日益认识到投资组合管理与风险控制的重要意义,并近乎成为他们的第一要务。本文利用因子模型,通过风险预算这一投资管理和风险控制技术与方法,讨论投资组合因子风险分解并进行实证分析。     

企业农产品电子商务能力测度的实证研究

低水平的农产品电子商务能力阻碍了农产品企业的可持续发展和创新。基于社会物质主义理论,构建企业农产品电子商务能力的模型,讨论农产品电子商务能力的内涵、形成机制和作用效果;并对316份企业样本数据,运用内容分析、问卷调查法和结构方程分析方法对理论模型进行实证检验。结果发现,农产品电子商务能力具有多维度结构,包含管理能力、技术能力和人才能力三个核心维度,且三者相互关联,共同对农产品电子商务能力产生作用。由此开发出量表以期为企业提升农产品电子商务能力提供一个可操作和量化的通用工具。     

基于学习动机感知的学生主体分类及其影响因素探究——以江苏省普通高校为实证

以大样本问卷调查为基础,采用多种数理统计方法,进行基于学习动机主观感知为学生主体类型划分及影响因素的研究。发现学习动机表征因素不止于内在和外在,还会体现在近期和远期、物质和精神、自我和他者等其他复杂要素上,而且还会受到入校时间、学校类型、性别以及地缘背景等因素影响。构建与学生主体需求相匹配的教育资源供给梯次和分类指导对促进高校教育具有重要意义。     

Marginal likelihood estimation from the Metropolis output: tips and tricks for efficient implementation in generalized linear latent variable models

The marginal likelihood can be notoriously difficult to compute, and particularly so in high-dimensional problems. Chib and Jeliazkov employed the local reversibility of the Metropolis–Hastings algorithm to construct an estimator in models where full conditional densities are not available analytically. The estimator is free of distributional assumptions and is directly linked to the simulation algorithm. However, it generally requires a sequence of reduced Markov chain Monte Carlo runs which makes the method computationally demanding especially in cases when the parameter space is large. In this article, we study the implementation of this estimator on latent variable models which embed independence of the responses to the observables given the latent variables (conditional or local independence). This property is employed in the construction of a multi-block Metropolis-within-Gibbs algorithm that allows to compute the estimator in a single run, regardless of the dimensionality of the parameter space. The counterpart one-block algorithm is also considered here, by pointing out the difference between the two approaches. The paper closes with the illustration of the estimator in simulated and real-life data sets.     

现代汉语“追累”句式的生成研究述评

"追累"是现代汉语中一种典型的多歧义动结式,有主语指向、宾语指向和施受颠倒三种解读,是汉语研究中的一个热点问题。近二十年来,"追累"句式的生成研究取得了丰硕的成果,但在复合词"追累"的生成方式上仍然存在较大争议。本文以这些争议为线索,对词汇生成论、词汇句法生成论和句法生成论等几种论点进行了评析,最后总结了相关研究所取得的成果并指出了今后有待进一步深入研究的几个问题。     

西部地区工业竞争力综合评价

本文基于面板数据的因子分析,从经济效益、科技与人才、能源与环保三个维度对西部十一省工业综合竞争力进行评估。结果表明,西部地区工业竞争力总体水平不高且不平衡明显。其中四川、重庆、陕西、广西、云南是西部具有较强的工业竞争力的地区,而贵州、甘肃、内蒙古、新疆、青海、宁夏竞争力较弱。因此要有针对性地实施发展规划,以促进西部地区工业差距缩小与总体发展水平的提升。     

A bibliographic study of public relations in Spanish media and communication journals, 2000–2012

This study analyses the trends and visibility of research on public relations in the most relevant Spanish media and communication journals between the years 2000 and 2012. Bibliometrics and content analysis are used to show the reduced presence of articles on public relations in these publications. A trend towards gender parity in authorship is confirmed in the sample, as well as a plurality of universities and a variety of research themes. The study also proves preference for generic questions rather than for specialised topics. Another finding is that almost one fourth of the specific articles on this discipline do not contain the term “public relations”. This can hint towards the need to have a specific high-impact publication on public relations to bring together and provide visibility to the contributions of researchers in this field.     

Complex Latent Variable Modeling in Educational Assessment

Bayesian item response theory models have been widely used in different research fields. They support measuring constructs and modeling relationships between constructs, while accounting for complex test situations (e.g., complex sampling designs, missing data, heterogenous population). Advantages of this flexible modeling framework together with powerful simulation-based estimation techniques are discussed. Furthermore, it is shown how the Bayes factor can be used to test relevant hypotheses in assessment using the College Basic Academic Subjects Examination (CBASE) data.     

Patience moderates the class cleavage in demand for redistribution

Previous studies on class voting have yielded mixed results linking income and demand for redistribution. Why do some poor people oppose redistribution, while some rich people support it? This article argues that an individual's level of patience, an important personal characteristic that influences how people calculate immediate and distinct outcomes, may moderate the effect of class on redistributive preference. In a one-shot game, redistribution between the rich and the poor is zero sum. When people extend their time horizons, however, the poor see the possibility of upward mobility, while the rich emphasize future losses, such as unemployment and economic instability. Consistent with the hypotheses, analyses of the 2014 Cooperative Congressional Election Study and a representative Taiwanese dataset from 2016 reveal a clear class cleavage in demand for redistribution among impatient poor and rich respondents, but the cleavage between their patient counterparts diminished. This pattern of convergence extends previous studies on upward mobility and risk perception theory.     

动态视角下中国城市群土地利用TFP测度及影响因素研究

提高城市群土地利用TFP对合理高效利用土地资源,协调好城市群经济发展、资源配置和环境保护具有重大理论和实践意义.文章运用DEA-Malmquist指数对2003—2016年动态视角下中国城市群土地利用TFP进行测度和时空演变分析,并利用Tobit回归模型对影响城市群土地利用TFP变化的因素进行深入研究.结果表明:从时间维度看,城市群土地利用TFP年均上升0.7％,城市群土地利用TFP增长由技术效率和技术进步"双核驱动",技术效率的提升主要与纯技术效率提升有关,规模效率是技术效率和土地利用TFP提升的瓶颈约束;从空间维度看,晋中、哈长、海峡西岸、中原、长江中游、北部湾、成渝、黔中、关中平原和兰西城市群土地利用TFP呈下降趋势,其余城市群土地利用TFP均呈上升趋势,且京津冀、呼包鄂榆、辽中南、长江三角洲、山东半岛和天山北坡城市群土地利用TFP增长为技术进步和技术效率"双核驱动";从影响因素看,人均GDP和年末金融机构人民币各项贷款余额对中国城市群土地利用TFP具有正向促进作用,城市财政支出占本市GDP的比重和人口密度具有负向阻碍作用.