Structural empowerment,psychological empowerment,and work engagement: A cross-country study

In this cross-country study we drew on job demands-resources theory to investigate whether psychological empowerment mediates the positive association between structural empowerment and work engagement and, consequently, task performance and intention to quit. A total of 1033 employees working in the service sector in Spain (N = 515) and the United Kingdom (N = 518) participated in the study. Multi-group structural equation modeling analyses revealed that psychological empowerment partially mediated the positive relationship between structural empowerment and work engagement, and that work engagement associated positively with task performance and negatively with intention to quit. Invariance analyses suggested that the positive link between psychological empowerment and work engagement was stronger for employees working in the UK than in Spain, providing support for partial structural invariance of the hypothesized model. These findings suggest that psychological empowerment is an underlying mechanism that may explain why structural empowerment relates positively to work engagement with implications for theory (i.e., extend the nomological network of the investigated constructs) and management practice (e.g., emphasize the role of structural empowerment for work design).     

机械装置转子支承系统临界转速估算K3法

根据机械振动和积木式传递矩阵法的原理,提出了用于估算单、双转子系统一阶临界转速的实用方法,从而得到的“K3表”可方便地使用于产品的方案设计阶段或现场排故,并可得到满意的工程精度。     

Causal inference with generalized structural mean models

Summary.  We estimate cause–effect relationships in empirical research where exposures are not completely controlled, as in observational studies or with patient non-compliance and self-selected treatment switches in randomized clinical trials. Additive and multiplicative structural mean models have proved useful for this but suffer from the classical limitations of linear and log-linear models when accommodating binary data. We propose the generalized structural mean model to overcome these limitations. This is a semiparametric two-stage model which extends the structural mean model to handle non-linear average exposure effects. The first-stage structural model describes the causal effect of received exposure by contrasting the means of observed and potential exposure-free outcomes in exposed subsets of the population. For identification of the structural parameters, a second stage 'nuisance' model is introduced. This takes the form of a classical association model for expected outcomes given observed exposure. Under the model, we derive estimating equations which yield consistent, asymptotically normal and efficient estimators of the structural effects. We examine their robustness to model misspecification and construct robust estimators in the absence of any exposure effect. The double-logistic structural mean model is developed in more detail to estimate the effect of observed exposure on the success of treatment in a randomized controlled blood pressure reduction trial with self-selected non-compliance.     

基于因果关系的教育研究方法思考

探索、检验因果关系是教育科学研究的重要目标之一,相关分析、回归分析、路径分析等常用统计方法存在许多不足。结构方程模型是针对这些不足提出来的,从统计思路上,它具有优点,但还不够完善,应引起我国教育学界的注意。     

刚体转动渐进跟踪控制的逆系统方法

逆系统方法是以非线性控制为目的,以直接分析为途径,以动态系统的逆概念为核心。该文将逆系统方法应用于刚体动力学中,运用非线性控制的逆系统方法设计Euler动力学方程的控制器,通过对一个陀螺的外力矩进行实施控制,使刚体在动坐标系下的角速度稳定跟踪指令,来实现对刚体转动的渐进跟踪控制。     

《诗经》叙事艺术特征阐释

叙事艺术在《诗经》中体现充分、反映显赫。本文从《诗经》所特有的现实主义诗风主题追求 ,以及叙事艺术的结构模式在《诗经》中体现两方面对叙事艺术特征进行阐释。也就是在题材和体裁两方面进行阐释 ,在题材上 ,表现出反映社会政治、人事、婚姻、爱情等方面内容。在体裁上 ,主要表现方式体现在叙事的抒发型、情节型、记实型这三类诗歌中。勾画出了叙事艺术在《诗经》中的轮廓 ,总结了叙事艺术在《诗经》中存在的方式。     

基于模仿者动力学模型的外在制度实施过程研究

外在制度在大群体组织中的实施是个复杂的过程.这一过程中,组织成员的理性程度较低而且行为相似,较适合用对称的模仿者动力学模型来分析.外在制度虽具有一定的自实施功能,但实施过程中实施者的主动性和创造性也很重要.借助于模型和案例分析,实施者可在现实中通过适当操作来控制实施环境,增强外在制度的实施效果.     

Detecting parameter shift in garch models

This paper applies recent theories of testing for parameter constancy to the conditional variance in a GARCH model. The supremum Lagrange multiplier test for conditional Gaussian GARCH models and its robustified variants are discussed. The asymptotic null distribution of the test statistics are derived from the weak convergence of the scores, and the critical values from the hitting probability of squared Bessel process.

Monte Carlo studies on the finite sample size and power performance of the supremum LM tests are conducted. Applications of these tests to S&P 500 indicate that the hypothesis of stable conditional variance parameters can be rejected.     

Pathways between education and health: a causal modelling approach

Summary.  The association of poor education and poor health has been consistently observed in many studies and in various countries. Thus far, studies examining the mechanisms underlying this association have looked at only a limited set of potential pathways. This study simultaneously examines six distinctive pathways, which have been hypothesized to link education and health and found support from previous studies. A causal analysis of education and health was performed using structural equation models. Data were used from six phases of the National Child Development Study, which is based on following up an initial sample of 17416 children who were born in 1958. The association between education and health appears to be explained by a combination of mechanisms: adolescent health and adult health behaviours for men and women, adult social class among men and parental social class among women. We conclude that improvements in population educational attainment may not automatically lead to improvements in population health, and that health policies for improving health and reducing health inequalities need to target specific causal pathways.     

要素禀赋、农户分化与农业价值链技术选择偏向

基于551份猕猴桃种植户调研数据,通过聚类分析方法将猕猴桃种植户分成发展型、规模种植型、劳动力富裕型三类,实证检验种植户类型对有机肥施用、新品种采纳、猕猴桃网络销售三个价值链技术活动选择的异质偏向性,分析农机补贴、产业组织检测、技术培训三个组织支持变量的调节效应。结果发现：发展型对于三个价值链技术活动及其联合采纳的选择偏向性高于其他类型,劳动力富裕型种植户对价值链技术活动的选择偏向性低于其他两个类型种植户。三个组织支持变量对同一类型种植户参与不同价值链技术活动以及不同类型种植户参与同一价值链技术活动的影响具有异质性。因此,针对不同类型价值链技术活动参与特征以及组织支持调节作用提出相应的政策建议。