Psychological Expertise and the Role of Individual Differences: An Exploration of Issues

Cognitive scientists have suggested that individual differences are relatively unimportant in predicting who will become an expert in any particular domain. This stance is at variance with the admissions screening practices of graduate programs in professional psychology as well as with counseling psychology's individual differences tradition. The purpose of this article was to consider some of the issues involved on both sides of this apparent contradiction, with particular emphasis on expertise in professional psychology. I first examine some of the possible operational definitions of expertise in this domain. I then consider salient literature and conclude that there almost certainly are threshold levels of intellectual and interpersonal skills that trainees in professional psychology should have. Beyond these levels, though, it may be that motivation and persistence are the most important variables in predicting the eventual attainment of expertise in professional psychology.     

基于Ajax自适应考试系统的设计与实现

Ajax是Web2.0的重要技术内容,它创建接近本地桌面应用的直接、高可用、更丰富、更动态的Web用户界面。计算机化自适应考试是现代测验研究中的一个新领域,它对于提高测验效率与质量有着重要意义。在考试系统项目中使用Ajax技术和计算机自适应原理,能有效提高系统的稳定性、快速反应能力。     

Types and Qualities of Knowledge and their Relations to Problem Solving in Physics

Based on empirical findings and theoretical considerations related to the field of expertise research, the importance of “types” and “qualities” of knowledge in relation to problem solving in physics was investigated. The students (N =138) in this study had a level of competence that corresponds to an intensive beginner college course in physics. It was found that conceptual declarative knowledge and problem scheme knowledge are excellent predictors of problem solving performance. However, a detailed analysis shows that the first knowledge type is more typical for low achievers (novices) in physics problem solving whereas the second type is predominately used by high achievers (experts). Regarding types and qualities of knowledge and their relations to problem solving, the results of a multidimensional scaling analysis (MDS) indicate that two dimensions of knowledge can be distinguished. On the extreme limits of the first dimension, which could be named “problem solving relevance vs. structure of discipline”, are the types of knowledge and the qualities of knowledge, respectively. The second dimension of knowledge could be named “single knowledge elements vs. organised knowledge units”. There are types of knowledge as well as qualities of knowledge distributed along this dimension. Consequences of these results for improving physics education are discussed.     

设计最优化学习环境:OECD研究的视角

设计最优化学习环境是面向21世纪的"适应性教育"所提出的要求,它有助于学习者形成"适应性能力"。OECD的研究认为,要善于提炼新学习的基本特征,这就是主动建构、自我调节、情境相依和协同努力。与此相连的新学习本质观主张:在学习过程中学习者应积极投身于学习活动中,持续努力,确保成功;重视学习者已有知识,强化知识组织,形成合理的知识结构与线索,形成一种完整的知识图景;遵循信息加工能力的限制条件,重视学习中动机、情感与认知的动态交互;培养学习者理解概念、通晓程序和自我调节的协调能力,致力于达到学习迁移的效果。为此,设计最优化学习环境的基本原则是:生本教学、自我调节;注重交往、善用合作;关注动机、情知相依;利用旧知、因人施教;富有挑战、减负增效;紧扣目标、不断反馈;学科融合和内外互通。     

快速、准确的图像阈值分割新方法

图像分割是数字图像处理系统中基本而关键的技术.通过阈值分割是其最简单的技术,它假设目标和背景是可以分离的.详细讨论将自适应遗传算法与OTSU算法相结合应用于最佳阈值的确定中,提出了相应的算法并用于图像分割,由于自适应遗传算法具有全局搜索最优解能力,因此能在很短时间内自动确定阈值.实验仿真结果表明,该方法不仅可以实现准确的图像分割,并且使得分割速度大大提高.     

Conceptions of giftedness and expertise put to the empirical test

Recent handbooks of giftedness or expertise propose a plethora of conceptions on the development of excellent performance but, to our knowledge, there are no comparative studies that provide empirical evidence of their validity to guide researchers and practitioners in their adoption of a particular conception. This study sought to close that gap by conducting an empirical comparison of the major approaches to giftedness and expertise currently in use: the IQ model, the performance model, the moderator model, and the systemic model. The four models were tested in a longitudinal study with a sample of N = 350 German students attending university preparatory schools; 25% of the sample had been assigned to special classes for the gifted. The construct and predictive validity of the four models were tested by means of structural equation modeling. Theoretical considerations along with our results indicated a differentiation among the models whereby some could only predict while others could also explain the emergence of excellent performance and thereby yield valuable information for the design of interventions. The empirical comparison of the approaches showed that they were unequally suited for the two challenges. For prediction purposes, the performance approach proved best while, for explanations, the moderator and systemic approaches were the most promising candidates. Even so, the latter did demonstrate conceptual and/or methodological problems. The IQ approach was superseded by the other approaches on both prediction and explanation. Implications and limitations of the findings are discussed.     

基于聚集密度的自适应选择多目标进化算法

分析了线性选择方法的两个缺陷,提出了一种基于聚集密度的非线性自适应选择方法。算法基本思想是：首先将每代种群划分成Pareto劣解集和Pareto非劣解集,然后依照个体的聚集密度分别在劣解集和非劣解集中构造一种偏序集,分别按照不同的等概率在这两个偏序集中选择个体,其中劣解偏序集的个体选择概率远小于非劣解偏序集的个体选择概率,根据两个偏序集中的容量自动计算出两个选择概率。这种非线性选择方法既体现了劣解集和非劣解集中个体的绝对平等性及非劣解集对劣解集的相对优先选择权,又充分考虑到了Pareto最优解的分布性。理论分析和数值计算表明,这种新的选择机制不仅能改善排序选择法的收敛性,而且能得到分布性良好的Pareto最优解。     

Stancetaking and Language Ideologies in Heritage Language Learner Classroom Discourse

Drawing on linguistic anthropological notions of language ideologies and sociolinguistic approaches to stance, this study examines the meaning-making resources through which Spanish heritage language (HL) learners orient toward ideological perspectives on language value and linguistic expertise in classroom interaction. Part of a larger ethnographic study, data in the present study include about 26 hours of audio and video recordings from three different intermediate Spanish HL classrooms and filmed interviews with the students. The analysis indicates that discourses of legitimacy and expertise are embodied within multiple levels of classroom interaction, including affective stancetaking, expert/novice positioning, and the reframing of both ascribed social positions and previous discourse. Results suggest that the role of language ideologies in HL learning can be better understood through an examination of stancetaking in interaction and that the construction of different kinds of expertise should be an important consideration in the development of HL instructional practices.     

Adaptive progressive download based on the MPEG-4 file format

In this paper we describe how progressive download and adaptive streaming can be combined into a simple and efficient streaming framework. Based on the MPEG-4 file format (MP4) we use HTTP for transport and argue that these two components are sufficient for specifying an open streaming architecture. The client selects appropriate chunks from the MP4 file to be transferred based on (1) the header information (i.e. the "moov" box) in the first part of the file and (2) his observation of network throughput. The framework is completely client driven which allows for better server scalability and reduces signalling overhead. We discuss architecture and implementation issues such as complexity, interoperability and scalability and compare to 3GPP PSS Re1-6 adaptive streaming when appropriate. Measurements from a simple MP4/HTTP streaming client are presented showing that appropriate chunks are selected such that increased reliability is achieved.     

Perceptual-cognitive expertise of handball coaches in their young and middle adult years

There is little research investigating the maintenance of perceptual-cognitive expertise in general and even less comparing coaches of different ages. The aim of this study was to test for perceptual-cognitive differences between age groups, licence levels, and their interaction. This study investigated differences in skilled performance between young and middle-aged coaches of three different skill levels. Participants performed an accuracy-oriented pattern recall (mean distance in pixel) and a time-oriented flicker test (mean detection time in ms). There were some significant differences between age groups and between skill groups for both tests, but no interactions. For the pattern recall test, the effect sizes were larger for skill level differences, while for the flicker test effects were larger for ageing. These results suggest coaches are able to maintain accuracy skills better than reaction timed tasks. This is in line with findings on speeded performance in general populations, which show declines with age. Moreover, results also support findings on perceptual expertise in skills where accuracy was important.