A bayesian alternative to least squares and equal weighting coefficients in regression

This paper details a Bayesian alternative to the use of least squares and equal weighting coefficients in regression. An equal weight prior distribution for the linear regression parameters is described with regard to the conditional normal regression model, and resulting posterior distributions for these parameters are detailed. Some interesting connections between this Bayesian procedure and several other methods for estimating optimal weighting coefficients are discussed. In addition, results are presented of a Monte Carlo investigation which compared the effectiveness of the Bayesian procedure relative to least squares, equal weight, ridge, and Bayesian exchangeability estimations.     

Contextual effects on number-time interaction

Time perception has long been known to be affected by numerical representations. Recent studies further demonstrate that when participants estimate the duration of Arabic numbers, number magnitude, though task-irrelevant, biases duration judgment to produce underestimation for smaller numbers and overestimation for larger numbers. Such effects were found in the present study to be significantly reduced when a weight unit gram was suffixed to the numbers rendering the mental magnitude differences between different numbers less distinctive. The effects were enhanced when a different unit kilogram was suffixed to the numbers enlarging the perceived magnitude differences between different numbers. The results indicate that effects of number magnitude on duration estimation should not be attributed to the mathematical differences between numbers but to how the numbers are perceived to differ from each other in magnitude in specific contexts when they denote concrete items. The results also provide new evidence for the theoretical proposal of a common generalized magnitude system and indicate that the system must be extended to include other action-oriented magnitudes, such as weight.     

On the existence and uniqueness of maximum-likelihood estimates in the Rasch model

Necessary and sufficient conditions for the existence and uniqueness of a solution of the so-called unconditional (UML) and the conditional (CML) maximum-likelihood estimation equations in the dichotomous Rasch model are given. The basic critical condition is essentially the same for UML and CML estimation. For complete data matricesA, it is formulated both as a structural property ofA and in terms of the sufficient marginal sums. In case of incomplete data, the condition is equivalent to complete connectedness of a certain directed graph. It is shown how to apply the results in practical uses of the Rasch model.Paper read at the European Meeting of the Psychometric Society, Groningen, June 19–21, 1980.Part of the research reported herein was done while the author was staying at the Pulmologisches Zentrum der Stadt Wien; he is indebted to Professor Dr. F. Muhar and Dr. R. Mutschlechner for providing excellent working conditions.     

贝叶斯结构方程模型及其研究现状

在心理学研究中结构方程模型(Structural Equation Modeling, SEM)被广泛用于检验潜变量间的因果效应, 其估计方法有频率学方法(如, 极大似然估计)和贝叶斯方法两类。近年来由于贝叶斯统计的流行及其在结构方程建模中易于处理小样本、缺失数据及复杂模型等方面的优势, 贝叶斯结构方程模型发展迅速, 但其在国内心理学领域的应用不足。主要介绍了贝叶斯结构方程模型的方法基础和优良特性, 及几类常用的贝叶斯结构方程模型及其应用现状, 旨在为应用研究者介绍新的研究工具。     

音乐表演训练对神经可塑性的影响:元分析研究

音乐表演是人类最复杂和精细的技能之一。通过激活似然性评估元分析,对音乐表演训练所诱发的神经可塑性进行探究。结果发现,音乐表演者与非音乐家在左侧小脑、双侧中央前回、双侧颞上回、左侧额下回、双侧顶下小叶以及右侧脑岛等脑区存在差异。这些脑区与听觉、运动以及多通道信息整合等加工有关。未来研究应从不同音乐表演训练诱发的神经适应性出发,进一步探究音乐表演训练与大脑可塑性之间的关联。     

A Structural Equation Analysis of the Wide Range Assessment of Memory and Learning in a Clinical Sample

A maximum likelihood confirmatory factor analysis was performed by applying LISREL VII to the Wide Range Assessment of Memory and Learning (WRAML) in a clinical sample (N = 271). Analyses were designed to determine which of 10 hypothesized oblique factor solutions could best explain memory as measured by the WRAML. Competing latent variable models were identified in previous studies and monographs on memory. Findings supported a three-factor model including Verbal Memory, Visual Memory, and Attention/Concentration factors. Our results are consistent with previous studies suggesting that attention is an important component of memory as measured by the WRAML. This study replicates previous research in which the Learning Index was not empirically supported.     

小脑与发展性阅读障碍

发展性阅读障碍是学龄儿童面临的学习问题之一。近年来,许多行为和神经生理学、影像学实验都发现,发展性阅读障碍的儿童有明显的运动功能失调,如平衡性差、身体灵敏度不够以及自动化水平低。Nicolson等人提出的小脑理论认为,阅读障碍者的小脑功能失调影响了书写及发音,导致语音及阅读能力不足,而且小脑与时间控制有关,阅读障碍者的时间估计能力有缺陷与他们的小脑功能失调有关。本文回顾了有关小脑理论的研究,并指出小脑的认知功能还有待进一步的研究。     

基于RSM对Q矩阵相同的无锚题测验的等值

传统锚题-非等组设计下的测验等值,等值要求的满足具有主观性,并且由于锚题失效或难以获得等因素的影响,则该方法的使用受到了限制。因此,本研究基于规则空间模型的Q矩阵理论,生成两个Q矩阵相同但无锚题的测验的共同受测者,使用共同组设计,利用同时性估计的方法对测验进行等值,并考虑了作答失误率和测验结构对等值稳定性的影响。结果表明:共同组设计同时估计方法的等值稳定性取得了优于或等于锚题-非等组同时估计方法;失误率的增大也会导致等值稳定性的下降;并且不同的测验结构也对等值稳定性产生了影响,其中直线型和收敛型结构稳定性较好,发散型和无结构型较差。     

遮挡范式下运动速度和方向对碰撞时间估计绩效指标的影响

为探索运动速度和方向对碰撞时间（TTC）估计的影响,采用3运动速度×4运动方向的双因素设计开展了实验研究。结果发现,在相对慢速条件下,受试者TTC估计的准确性显著差于相对中速和相对快速条件;仅在相对慢速条件下受试者对竖直方向的TTC估计准确度显著差于水平方向、低估TTC的比例显著高于高估TTC的比例。结果表明,运动速度对TTC估计绩效指标的影响相对较强,运动方向对其影响相对较弱;两个因素的影响存在交互作用。