个体解决三项系列问题的心理模型

该研究设计了2种实验条件,对360名6-19岁个体解决三项系列问题的能力发展进行了研究,旨在讨论个体解决三项系列问题的心理模型的发展问题,结果表明：(1)6-19岁个体对三项系列问题中有必然逻辑答案的题目的判断能力的发展速度比较平稳;(2)个体对三项系列问题中有必然逻辑答案的题目的判断能力先于对没有逻辑答案的题目,6-9岁个体对三项系列问题中没有必然逻辑答案的题目的判断能力的发展速度低于10岁以后的个体;(3)空间模型、语义模型、语义一空间混合模型和枢纽项比较模型是相互补充的,是在不同认知发展阶段依一定次序,按一定的阶段逐渐形成的,经历了5个不同的发展阶段,最终形成以枢纽项比较模型为核心、四种心理模型并存于个体的心理结构之中的复合模型。     

疼痛恐惧对疼痛的影响及其认知机制

疼痛恐惧是把将要出现的疼痛刺激视为主要威胁而产生的一种恐惧,它会影响与疼痛相关的感知觉、注意、回避行为以及安慰剂止痛的效果.疼痛恐惧的认知模型主要有活动回避模型、恐惧-回避模型以及内感受性恐惧条件模型.未来的研究要进一步探究疼痛恐惧的认知机制,完善疼痛恐惧的认知模型并扩展疼痛恐惧的研究方法.     

颜色知觉恒常理论的回顾

本文对早期颜色恒常理论、系数理论、计算理论和 Octant模型作了简要回顾 ,并结合已有的研究成果进行评述。对影响颜色恒常性机制的主要因素进行了探讨。强调了知觉经验、记忆、认知决策等高级意识活动对颜色恒常知觉的作用 ,并尝试性地提出了描述颜色恒常知觉过程的一般参照框架。     

Constrained maximum likelihood estimation of two-level covariance structure model via EM type algorithms

In this paper, the constrained maximum likelihood estimation of a two-level covariance structure model with unbalanced designs is considered. The two-level model is reformulated as a single-level model by treating the group level latent random vectors as hypothetical missing-data. Then, the popular EM algorithm is extended to obtain the constrained maximum likelihood estimates. For general nonlinear constraints, the multiplier method is used at theM-step to find the constrained minimum of the conditional expectation. An accelerated EM gradient procedure is derived to handle linear constraints. The empirical performance of the proposed EM type algorithms is illustrated by some artifical and real examples.This research was supported by a Hong Kong UCG Earmarked Grant, CUHK 4026/97H. We are greatly indebted to D.E. Morisky and J.A. Stein for the use of their AIDS data in our example. We also thank the Editor, two anonymous reviewers, W.Y. Poon and H.T. Zhu for constructive suggestions and comments in improving the paper. The assistance of Michael K.H. Leung and Esther L.S. Tam is gratefully acknowledged.     

An alternating least squares method for the weighted approximation of a symmetric matrix

Bailey and Gower examined the least squares approximationC to a symmetric matrixB, when the squared discrepancies for diagonal elements receive specific nonunit weights. They focussed on mathematical properties of the optimalC, in constrained and unconstrained cases, rather than on how to obtainC for any givenB. In the present paper a computational solution is given for the case whereC is constrained to be positive semidefinite and of a fixed rankr or less. The solution is based on weakly constrained linear regression analysis.The authors are obliged to John C. Gower for stimulating this research.     

Decomposition,Interdependence and Precision in Multiattribute Utility Measurements

Traditionally, parameters of multiattribute utility models, representing a decision maker's preference judgements, are treated deterministically. This may be unrealistic, because assessment of such parameters is potentially fraught with imprecisions and errors. We thus treat such parameters as stochastic and investigate how their associated imprecision/errors are propagated in an additive multiattribute utility function in terms of the aggregate variance. Both a no information and a rank order case regarding the attribute weights are considered, assuming a uniform distribution over the feasible region of attribute weights constrained by the respective information assumption. In general, as the number of attributes increases, the variance of the aggregate utility in both cases decreases and approaches the same limit, which depends only on the variances as well as the correlations among the single-attribute utilities. However, the marginal change in aggregate utility variance decreases rather rapidly and hence decomposition as a variance reduction mechanism is generally useful but becomes relatively ineffective if the number of attributes exceed about 10. Moreover, it was found that utilities which are positively correlated increase the aggregate utility variance, hence every effort should be made to avoid positive correlations between the single-attribute utilities. We also provide guidelines for determining under what condition and to what extent a decision maker should decompose to obtain an aggregate utility variance that is smaller than that of holistic assessments. Extensions of the current model and empirical research to support some of our behavioural assumptions are discussed. © 1997 John Wiley & Sons, Ltd.     

积极与消极情绪关系的理论及研究

积极与消极情绪的关系一直是情绪领域中最引人注目的焦点之一。该文介绍了探讨积极与消极情绪关系的模型及相关的证据,包括以下4个方面的内容：（1）情绪的双极模型及相关证据;（2）情绪的双变量模型及相关证据;（3）情绪的混合模型及相关证据;（4）解决各种模型争论的新视角：条件决定论。文章最后分析了该领域研究的不足,并提出了未来研究的方向     

年老化与文本理解

年老化与文本理解的研究表明,老年人在表层形式和文本基础两个低水平表征上的理解和记忆能力下降,而在情境模型的建构和提取、更新等加工过程中都没有发现由于年老化引起的能力下降。在介绍这些研究的基础上,从情境模型与另两个低水平加工的不同特点和老年人自身的特殊性两个方面分析了老年人在不同层次表征水平加工能力差异的原因。对情境模型水平加工能力保持的潜在机制及相关的影响因素,以及如何弥补在低水平加工中认知能力因年龄而产生的下降等问题还需要进行探讨     

教师资格和职业发展因素对学生数学成绩的影响：一个跨文化比较

采用TIMSS2003中的数据,应用混合模型,比较香港、日本、瑞典和美国四个国家(地区)教师资格因素和职业发展因素对其学生数学学业成绩的影响。结果发现香港教师高学历和常有其他教师听课提高了学生成绩;瑞典教师的性别、专业和参加数学教学方法方面的职业发展活动,以及美国教师的专业和听其他教师讲课显著影响其学生成绩;日本教师资格和职业发展因素对其学生成绩没有影响。