Higher-order latent trait models for cognitive diagnosis

Higher-order latent traits are proposed for specifying the joint distribution of binary attributes in models for cognitive diagnosis. This approach results in a parsimonious model for the joint distribution of a high-dimensional attribute vector that is natural in many situations when specific cognitive information is sought but a less informative item response model would be a reasonable alternative. This approach stems from viewing the attributes as the specific knowledge required for examination performance, and modeling these attributes as arising from a broadly-defined latent trait resembling theϑ of item response models. In this way a relatively simple model for the joint distribution of the attributes results, which is based on a plausible model for the relationship between general aptitude and specific knowledge. Markov chain Monte Carlo algorithms for parameter estimation are given for selected response distributions, and simulation results are presented to examine the performance of the algorithm as well as the sensitivity of classification to model misspecification. An analysis of fraction subtraction data is provided as an example. This research was funded by National Institute of Health grant R01 CA81068. We would like to thank William Stout and Sarah Hartz for many useful discussions, three anonymous reviewers for helpful comments and suggestions, and Kikumi Tatsuoka and Curtis Tatsuoka for generously sharing data.     

Role models in career development: New directions for theory and research

Career theory proposes the importance of role models as helping to guide individual development. Furthermore, the media often depict role models as essential to career success. However, research on role models as a construct distinct from developmental relationships with mentors and behavioral models has waned. This article makes the case for reinvigorating the role model construct. A revised definition is provided, depicting role models as cognitive constructions based on an individual’s needs, wants, and ambitions. Drawing on recent advances in social comparison and self-concept theories, a dimensional approach to role models integrates current theory and research, suggesting that role models should be construed along two cognitive dimensions (positive/negative, global/specific), and two structural dimensions (close/distant, up/across-down). The article concludes by suggesting new research directions prompted by this new view of the role model construct.     

Processing speed, intelligence, creativity, and school performance: Testing of causal hypotheses using structural equation models

According to mental speed theory of intelligence, the speed of information processing constitutes an important basis for cognitive abilities. However, the question, how mental speed relates to real world criteria, like school, academic, or job performance, is still unanswered. The aim of the study is to test an indirect speed-factor model in comparison to rivaling models explaining the relationships between different mental abilities and performance. In this speed-factor model, basic cognitive processing is assumed to influence higher mental abilities (IQ and creativity). Intelligence and creativity themselves should be valid predictors of school performance. We computed bivariate correlations and structural equation models to test this hypothesis, using indicators of processing speed [Zahlen-Verbindungs-Test (ZVT) and Coding Test], psychometric intelligence [Kognitiver Fähigkeits-Test (KFT) and Raven's Advanced Progressive Matrices (APM)], creativity [Verbaler Kreativitäts-Test (VKT) and Verwendungs-Test (VWT)] and school performance (grades). In a sample of 271 students from German gymnasiums (Class Levels 9 to 11) the speed-factor model can reproduce at best the empirical relationships between processing speed, intelligence, creativity, and school performance: It assumes that processing speed influences higher mental abilities (intelligence and creativity), which, in the sequel, influence school performance. Therefore, processing speed seems to have no direct effect on school performance; the effect is indirect as it operates via mediation through higher cognitive abilities.     

Consumers Felt Commitment Towards Retailers: Index Development and Validation

This work seeks to develop an index of the consumer's felt commitment towards the retailer through a formative scale. By using structural equation modeling (SEM), in particular the multiple indicators and multiple causes (MIMIC) model, as well as reflective and formative indicators, the methodology developed by Diamantopoulos and Winklhofer is applied in order to construct this index. To clarify the whole meaning of the concept, the article undertakes a thorough review of literature on felt commitment and formative index development. Several MIMIC models are developed in order to validate the index. The empirical study was carried out in the financial services sector.     

Affect, Curiosity, and Socialization-Related Learning: A Path Analysis of Antecedents to Job Performance

This study examined the influence of affect, curiosity, and socialization-related learning on job performance, with 233 service industry employees from a diverse variety of occupations completing surveys at their places of work. Both state and trait curiosity and socialization-related learning (learning associated with employee socialization) were hypothesized to mediate the relationship between affect (operationalized as state and trait anxiety and anger) and job performance. Structural equation analyses indicate that the data are consistent with the theoretical models proposed. As expected, anxiety negatively influences curiosity, socialization-related learning, and job performance; conversely, anger positively influences curiosity, socialization-related learning, and job performance. Overall, the findings suggest that affects indeed predict perception of job performance, but through the mediation of curiosity and the learning associated with the socialization process. These results highlight the importance of the complex interplay between affect, curiosity, and learning when thinking about successful employee socialization and best possible job performance.     

应用Markov模型进行临床决策分析的思考

应用模型进行临床决策分析的研究日益增多,Markov模型就是近年来用于临床决策分析的一种.它优于传统的决策树分析方法,能应用于疾病预后影响因素的研究、筛查试验的评价、疾病治疗结局预测、纵向生命质量资料分析等多个方面.Markov模型用于临床决策分析,是创新思维的体现,是实事求是的典范,体现了认识的辩证过程.     

心、脑科学与医学人道主义价值观

当今,心、脑科学的研究进展及成果极大支持了科学的医学人道主价值观应当以正确认识、把握、运用脑模式科学假说为基础的观点.试从意识的本质、医学人道价值观的机制、与价值相关的医者心灵的自我控制和意志自由等三个方面探讨心、脑科学同医学实践中的医学人道价值观的关系.     

重新构建先天性心脏病的学科新模式

现有先天性心脏病防治模式存在明显不足.为了更加有利于患者的治疗及先心病的学科发展,建议重新构建先心病学科新模式,将先心病独立成科,内外科融为一体,使先心病学科向专业化发展.     

一种特殊的计算机指点装置追踪球的操作活动研究

探讨在指点定位中目标方向、大小和距离对食指和拇指操纵追踪球的运动时间的效应 ,并由此建立了两种追踪球的菲茨模型。用绩效指数比较了不同指点装置的操作绩效 ,对追踪球的优化设计提出了建议。     

第二语言语义提取中的工作记忆效应

本文报告一项针对工作记忆容量是否制约中国英语学习者第二语言语义提取效率的实验。实验考查了工作记忆广度中的个体差异是否抑制学习者对第二语言单词语义信息的提取问题,还探索了工作记忆广度和第二语言词汇知识水平的相关性。研究以通用容量工作记忆模型为基础,采用运算广度的工作记忆测试,得出工作记忆广度对单词语义信息的提取没有显著抑制作用的结果。结果还显示工作记忆广度与第二语言词汇知识水平之间没有显著的线性关系。