Temporal pattern in number of staff on sick leave: the effect of downsizing

Summary.  The pattern of absenteeism in the downsizing process of companies is a topic in focus in economics and social science. A general question is whether employees who are frequently absent are more likely to be selected to be laid off or in contrast whether employees to be dismissed are more likely to be absent for the remaining time of their working contract. We pursue an empirical and microeconomic investigation of these theses. We analyse longitudinal data that were collected in a German company over several years. We fit a semiparametric transition model based on a mixture Poisson distribution for the days of absenteeism per month. Prediction intervals are considered and the primary focus is on the period of downsizing. The data reveal clear evidence for the hypothesis that employees who are to be laid off are more frequently absent before leaving the company. Interestingly, though, no clear evidence is seen that employees being selected to leave the company are those with a bad absenteeism profile.     

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.     

言语生成及理解的心理模型

言语生成 (speechproduction)和言语理解 (speechunderstanding)是语言交际中十分复杂的心理认知过程 ,也是心理语言学研究中的一个重要内容。本文拟对有关言语生成和理解的几种心理模型予以讨论 ,探讨言语生成及理解的过程和实质。     

密度分布非均匀的反馈控制Logistic单种群模型平衡态的稳定性

本文对种群密度在非均匀分布情形下,考虑了具反馈控制的滞后 Logistic 生态模型平衡位置的稳定性;分别给出了在常时滞和弱连续时滞以及强连续时滞情况下的稳定性条件;其结果是对 Gopalsamy 在密度均匀分布情形下相应结果的推广.     

管理沟通在高校图书馆工作中的应用

高校图书馆在高校师生心目中应有极其重要的位置,在高校的教学、科研工作中应有极其重要的作用,但现实与期望总会有一定的差距。面对差距,高校图书馆内部应充分应用管理沟通的原理与方法,作好图书馆领导层与馆员之间、馆员与馆员之间以及馆员与读者之间的沟通和交流,处理好与各方的关系,弥补来自各方的认识偏差和自身工作的不足,提升高校图书馆的声望与地位。     

网络交往中真实性的社会学分析

在网络交往中,其交往媒介的表意性、交往主体的平等性、交往互动的开放性、交往管理的规范性都是不同于现实的社会交往的,其交往过程中不仅有虚拟性的一面,而且也有其真实性的一面。网络交往中的真实性对我们具有升华社会交往、促进人的社会化、丰富社会日常生活等方面的意义。     

Residual analysis for spatial point processes (with discussion)

Summary.  We define residuals for point process models fitted to spatial point pattern data, and we propose diagnostic plots based on them. The residuals apply to any point process model that has a conditional intensity; the model may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Some existing ad hoc methods for model checking (quadrat counts, scan statistic, kernel smoothed intensity and Berman's diagnostic) are recovered as special cases. Diagnostic tools are developed systematically, by using an analogy between our spatial residuals and the usual residuals for (non-spatial) generalized linear models. The conditional intensity λ plays the role of the mean response. This makes it possible to adapt existing knowledge about model validation for generalized linear models to the spatial point process context, giving recommendations for diagnostic plots. A plot of smoothed residuals against spatial location, or against a spatial covariate, is effective in diagnosing spatial trend or co-variate effects. Q – Q -plots of the residuals are effective in diagnosing interpoint interaction.     

An individual measure of relative survival

Summary.  Relative survival techniques are used to compare survival experience in a study cohort with that expected if background population rates apply. The techniques are especially useful when cause-specific death information is not accurate or not available as they provide a measure of excess mortality in a group of patients with a certain disease. Whereas these methods are based on group comparisons, we present here a transformation approach which instead gives for each individual an outcome measure relative to the appropriate background population. The new outcome measure is easily interpreted and can be analysed by using standard survival analysis techniques. It provides additional information on relative survival and gives new options in regression analysis. For example, one can estimate the proportion of patients who survived longer than a given percentile of the respective general population or compare survival experience of individuals while accounting for the population differences. The regression models for the new outcome measure are different from existing models, thus providing new possibilities in analysing relative survival data. One distinctive feature of our approach is that we adjust for expected survival before modelling. The paper is motivated by a study into the survival of patients after acute myocardial infarction.     

儒、释、道的人际交往观比较研究

人是自然属性和社会属性高度集中的统一体,社会生产关系是决定人际交往关系的决定因素。人们在社会生产生活中必然发生某种关系,可统称为人际关系或社会关系。儒家、佛教、道教均有其各自的人际交往理论和实践,认真总结儒、释、道三家人际交往的经验教训,是建设具有中国特色社会主义新文化的时代要求。     

Unexpected but authentic use of an ethnically–marked dialect

Recent work on language crossing in the U.S. has examined the temporary appropriation of African American Vernacular English by white youth in an effort to participate in the current popularity and prestige of hip–hop culture, or in order to highlight racial boundaries. While such verbal behavior probably encompasses most white use of AAVE, it is not the only way in which whites (or other non–blacks) can use the variety. This paper presents a case study of the language of a 23 year old white female who makes consistent use of many distinctive linguistic features associated with AAVE. I argue that the interaction of ideologies of race, class, localness and language allow her to be considered an ingroup member despite her biographical race. This suggests that there is a tension between academic linguistic theory and actual speaker practice in assigning authenticity to individuals, and I conclude that language ideologies and other forms of qualitative evidence should be taken into account by sociolinguists looking at the link between language and race.