Joint analysis of longitudinal data and competing terminal events in the presence of dependent observation times with application to chronic kidney disease

In many prospective clinical and biomedical studies, longitudinal biomarkers are repeatedly measured as health indicators to evaluate disease progression when patients are followed up over a period of time. Patient visiting times can be referred to as informative observation times if they are assumed to carry information in addition to that of the longitudinal biomarker measures alone. Irregular visiting times may reflect compliance with physician instruction, disease progression and symptom severity. When the follow-up time may be stopped by competing terminal events, it is possible that patient observation times may correlate with the competing terminal events themselves, thus making the observation times difficult to assess. To explicitly account for the impact of competing terminal events and dependent observation times on the longitudinal data analysis in the context of such complex data, we propose a joint model using latent random effects to describe the association among them. A likelihood-based approach is derived for statistical inference. Extensive simulation studies reveal that the proposed approach performs well for practical situations, and an analysis of patients with chronic kidney disease in a cohort study is presented to illustrate the proposed method.     

Tree‐Based Logistic Regression Approach for Work Zone Casualty Risk Assessment

This study presents a tree‐based logistic regression approach to assessing work zone casualty risk, which is defined as the probability of a vehicle occupant being killed or injured in a work zone crash. First, a decision tree approach is employed to determine the tree structure and interacting factors. Based on the Michigan M‐94\I‐94\I‐94BL\I‐94BR highway work zone crash data, an optimal tree comprising four leaf nodes is first determined and the interacting factors are found to be airbag, occupant identity (i.e., driver, passenger), and gender. The data are then split into four groups according to the tree structure. Finally, the logistic regression analysis is separately conducted for each group. The results show that the proposed approach outperforms the pure decision tree model because the former has the capability of examining the marginal effects of risk factors. Compared with the pure logistic regression method, the proposed approach avoids the variable interaction effects so that it significantly improves the prediction accuracy.     

引入制度和产业结构因素下的经济增长实证研究

本文在分析我国经济增长要素时,除选取传统的资本投入、劳动因素和人力资本作为解释变量外,还引入了制度因素和产业结构变量,通过建立变量间的回归模型并进行Granger因果检验和对变量的序列相关性及平稳性进行检验的基础上,建立了具有良好统计性质的协整与误差修正模型,较好地解释了影响我国经济增长的主要因素。     

用科学发展观反思历史发展,指导历史研究

科学发展观是当今时代与毛泽东思想、邓小平理论、“三个代表”重要思想一脉相承的马克思主义的理论创新。是我国建设中国特色社会主义的指导方针。它源于历史，用它来反思历史发展，指导历史研究，不仅具有历史意义。而且具有现实意义。     

俄语专业“零起点”视听说教学新探

本文重点分析俄语专业＂零起点＂学生视听说课程基础阶段的教与学。     

应用“高数CAI”开展电脑辅助教学初探

文章介绍了作者在高师【数学分析】课程教学中利用软件【高等数学CAI系统】进行电脑辅助教学的做法和体会．     

Economic growth and inequality in Singapore: The case for a minimum wage

In the context of Singapore's ageing population, the employment of large numbers of low‐skilled foreign workers is proving to be a major challenge to inclusive growth because of the stagnation of low‐wage workers' incomes. In order to address this problem, the author makes the case for introducing a minimum wage to complement existing in‐work benefit schemes. After addressing the commonly voiced objections to a minimum wage system, he suggests ways in which a minimum wage could be implemented in Singapore. New measures to enhance the social safety net and foster more sustainable economic growth are also proposed.     

创新网络背景下区域R & D支出的外部环境影响因素研究--基于省际面板数据的实证检验

创新网络形成后,区域内各创新主体的R&D支出与其他主体的行为息息相关,其R&D支出的总和在宏观上表现为区域R&D支出的核心内容。以此为背景,基于现有研究成果,构建数学模型,采用面板数据模型对2000~2009年的30个省市样本数据进行检验,研究区域R&D支出的外部环境影响因素。结果显示：在创新网络背景下,市场规模、市场结构、开放度以及技术引进等因素与区域R&D支出水平正相关,且相关程度依次递减;政府投入负向影响区域R&D支出,但影响的显著性水平并不高。研究成果对实现区域资源优化配置,提高区域创新绩效具有一定的理论意义和实用价值。     

重新认识质性研究在当下中国研究中的重要性——以人类学应用研究为例

以参与式田野研究和深度访谈为主要方法的人类学研究是质性研究的重要实践. 自上世纪末以来,我国社会人文学界出现了对"科学"的一种误读,将"科学"研究理解为"量化研究",甚至将"数字"视为科学性的最高表述,将应用研究中有无"数字"表述作为衡量其价值的标准.由于有些社会人文学者把"数字"当做拜物主义对象,以经验研究为主要方法,以质性研究(对社会结构、制度、关系以及社会文化意义等的探索)为目标的人类学,在社会人文应用研究中遭到了质疑,也因此又一次被边缘化.     

四通换向阀内泄漏分析研究

内泄漏量是衡量四通换向阀性能的重要指标之一,本文建立了四通换向阀的气体试验中的泄漏模型,并通过试验方法研究了坟差、气体温度对泄漏量的影响,理论和试验结果表明,在同一个换向阀上,压差的增加会明显地增加泄漏量,而气体温度的上升会使泄漏量降低。