Imputation of missing categorical data by maximizing internal consistency

This paper suggests a method to supplant missing categorical data by reasonable replacements. These replacements will maximize the consistency of the completed data as measured by Guttman's squared correlation ratio. The text outlines a solution of the optimization problem, describes relationships with the relevant psychometric theory, and studies some properties of the method in detail. The main result is that the average correlation should be at least 0.50 before the method becomes practical. At that point, the technique gives reasonable results up to 10–15% missing data.We thank Anneke Bloemhoff of NIPG-TNO for compiling and making the Dutch Life Style Survey data available to use, and Chantal Houée and Thérèse Bardaine, IUT, Vannes, France, exchange students under the COMETT program of the EC, for computational assistance. We also thank Donald Rubin, the Editors and several anonymous reviewers for constructive suggestions.     

Least-squares approximation of an improper correlation matrix by a proper one

An algorithm is presented for the best least-squares fitting correlation matrix approximating a given missing value or improper correlation matrix. The proposed algorithm is based upon a solution for Mosier's oblique Procrustes rotation problem offered by ten Berge and Nevels. A necessary and sufficient condition is given for a solution to yield the unique global minimum of the least-squares function. Empirical verification of the condition indicates that the occurrence of non-optimal solutions with the proposed algorithm is very unlikely. A possible drawback of the optimal solution is that it is a singular matrix of necessity. In cases where singularity is undesirable, one may impose the additional nonsingularity constraint that the smallest eigenvalue of the solution be , where is an arbitrary small positive constant. Finally, it may be desirable to weight the squared errors of estimation differentially. A generalized solution is derived which satisfies the additional nonsingularity constraint and also allows for weighting. The generalized solution can readily be obtained from the standard unweighted singular solution by transforming the observed improper correlation matrix in a suitable way.     

Adaptation, teleology, and selection by consequences

This paper presents and defends the view that reinforcement and natural selection are selection processes, that selection processes are neither mechanistic nor teleological, and that mentalistic and vitalistic processes are teleological but not mechanistic. The differences between these types of processes are described and used in discussing the conceptual and methodological significance of “selection type theories” and B. F. Skinner's radical behaviorist view that “operant behavior is the field of intention, purpose, and expectation. It deals with that field precisely as the theory of evolution has dealt with another kind of purpose” (1986, p. 716). The antimentalism of radical behaviorism emerges as a post-Darwinian extension of Francis Bacon's (and Galileo's) influential view that “[the introduction of final causes] rather corrupts than advances the sciences” (Bacon, 1905, p. 302).     

Rasch's multiplicative poisson model with covariates

As a multivariate model of the number of events, Rasch's multiplicative Poisson model is extended such that the parameters for individuals in the prior gamma distribution have continuous covariates. The parameters for individuals are integrated out and the hyperparameters in the prior distribution are estimated by a numerical method separately from difficulty parameters that are treated as fixed parameters or random variables. In addition, a method is presented for estimating parameters in Rasch's model with missing values. The author is now affiliated with the Otara University of Commerce. The author is grateful to Yoshio Takane, Haruo Yanai, Eiji Muraki, the editor and referees for their careful readings and helpful suggestions on earlier versions of this paper. Part of this work was presented at the third European Congress of Psychology at Tampere, Finland in 1993.     

时序信息提取机制的探索

对时序信息加工的经典研究是采用新近性判断范型,结果发现其提取机制是以新近性为基础的逆向串行搜索过程。本研究采用新近性判断范型和早远性判断范型对时序信息的提取机制进行了深入的考察,结果表明：（ｌ）提取时序信息既存在逆向串行搜索,又存在顺向串行搜索;（２）早远性判断和新近性判断任务对不同部分时序信息恢复的效应不同,其中早远性判断易化早远部分,新近性判断易化新近部分──表现为对相应部分辨别力的提高和正确反应潜伏期的缩短;（３）在不同的时序信息提取任务中,被试会根据具体条件进行反转反应。     

Maximum likelihood estimation of the joint covariance matrix for sections of tests given to distinct samples with application to test equating

Consider an old testX consisting ofs sections and two new testsY andZ similar toX consisting ofp andq sections respectively. All subjects are given testX plus two variable sections from either testY orZ. Different pairings of variable sections are given to each subsample of subjects. We present a method of estimating the covariance matrix of the combined test (X ₁, ...,X _s ,Y ₁, ...,Y _p ,Z ₁, ...,Z _q ) and describe an application of these estimation techniques to linear, observed-score, test equating.The author is indebted to Paul W. Holland and Donald B. Rubin for their encouragement and many helpful comments and suggestions that contributed significantly to the development of this paper.This research was supported by the Program Statistics Research Project of the ETS Research Statistics Group.     

语言产生中词频效应老化的神经基础与时间进程

词频效应指语言产生中人们对高频词汇的加工比低频词汇更快更准确的一种现象,它可能发生在语言产生中的不同阶段。对青年人和老年人词频效应的不同特点和加工机制进行比较,可以考察语言产生的认知老化机制。通过语言产生理论可对词频效应的老化进行预测,提出词频效应在个体发展和老化阶段的相对稳定性,分析老化导致词频效应相关的神经基础和加工时间进程的改变。未来研究可进一步分离词频效应与习得年龄效应对语言产生老化的影响,并扩展至神经退行性疾病患者中。     

催产素、孕激素和雌激素对厌恶的影响及其神经生理机制

厌恶是人和动物最基本的情绪之一,起源于口腔对苦味(有毒)物质的排斥,常伴有恶心呕吐和远离诱发刺激的强烈愿望,具有回避潜在疾病威胁的功能。大量动物和人类研究表明,催产素、孕激素和雌激素不同程度地影响核心厌恶刺激的感知、核心厌恶情绪的产生与表达、条件性厌恶习得和厌恶表情识别。三种激素主要通过作用于五羟色胺、γ-氨基丁酸、乙酰胆碱和谷氨酸等神经递质受体,调节杏仁核、脑岛、前扣带回、壳核、梨状皮层、额中回等脑区活动,影响厌恶加工。未来研究应当在准确测量激素水平和控制实验任务难度的基础上,探究各激素对不同感觉通道厌恶加工的影响,及其性别的调节作用;同时结合脑成像技术和动物行为学,明确各激素影响厌恶加工的神经内分泌机制。     

视觉空间伪忽视与表征伪忽视神经机制的异同

伪忽视是指个体存在的轻微偏左的不对称空间注意,而视觉空间伪忽视和表征伪忽视是其两种主要表现形式。研究初期,研究者认为两种伪忽视基于相同的注意定向左偏机制,但近年来研究发现,它们存在神经机制的差异。本文主要从两种伪忽视神经机制的异同出发,梳理近期研究结果,以期增进对伪忽视的理解。未来研究可以从认知时间进程角度或设计更为完善的研究范式进一步探讨这两种伪忽视神经机制的异同。     

我国市场经济"信用"动力机制分析及其体系建构

现代社会生活的生产实践表明,分工是交换的前提,交换是分工的实现,这就是现代社会活动的全部内容和过程。在此事实基础上构建的市场经济体制,其管理理念内含着丰富的伦理意蕴[1]。本文首先分析阐述了市场经济信用体系的建立是市场经济体制内在规律的必然要求,揭示了“信用”是承诺者之间能量均衡与博弈的结果,既具有丰富的道德理性又具有明显的功利要求。文章进而通过对信用体系维护的动力因素及其与市场主体行为的相关性进行比较研究后指出:政府在参与市场经济活动中要坚持“有所为,有所不为”,应把政府置于经济利益之外,使之具有超脱于市场各成员的地位;同时,信用体系的创立和维护并不必然由政府主导,而是市场经济环境中公共合意选择的必然结果。