A Computationally Efficient State Space Approach to Estimating Multilevel Regression Models and Multilevel Confirmatory Factor Models

Although the state space approach for estimating multilevel regression models has been well established for decades in the time series literature, it does not receive much attention from educational and psychological researchers. In this article, we (a) introduce the state space approach for estimating multilevel regression models and (b) extend the state space approach for estimating multilevel factor models. A brief outline of the state space formulation is provided and then state space forms for univariate and multivariate multilevel regression models, and a multilevel confirmatory factor model, are illustrated. The utility of the state space approach is demonstrated with either a simulated or real example for each multilevel model. It is concluded that the results from the state space approach are essentially identical to those from specialized multilevel regression modeling and structural equation modeling software. More importantly, the state space approach offers researchers a computationally more efficient alternative to fit multilevel regression models with a large number of Level 1 units within each Level 2 unit or a large number of observations on each subject in a longitudinal study.     

Hydrogen-induced cold cracking in heat-affected zone of low-carbon high-strength steel

The Y-groove cracking test by submerged arc welding was employed to study the susceptibility of a low-carbon high-strength steel to hydrogen-induced cold cracking (HICC). The morphology of hydrogen cracks was observed using an electron probe microscope. The results showed that the heat-affected zone (HAZ) has a higher susceptibility to HICC than the weld metal and that increasing heat input can improve the HICC resistance of the weldment. The intergranular microcracking is the main HICC mode at the lowest heat input condition, accompanied with some transgranular microcracks attached to complex inclusions. In combination with phase transformation behaviour in sub-zones, the effect of the phase transformation sequence is proposed to try to illustrate the fact that the fine-grained HAZ has higher probability of hydrogen cracking than the coarse-grained HAZ owing to the occurrence of hydrogen enrichment in the fine-grained HAZ after the transformation.     

通货膨胀知觉的认知机制和影响因素

通货膨胀知觉是个体对通货膨胀的主观体验.通货膨胀知觉的认知机制主要体现在体验阶段和整合阶段.体验阶段主要涉及到个体对物价的感受性和记忆,整合阶段主要涉及到个体利用可得性启发式以及锚定和调整启发式完成对通货膨胀的最终估计.通货膨胀知觉的影响因素主要包括通货膨胀预期、框架效应、对价格公平性的认知、社会放大效应以及货币改革等.未来可以从通货膨胀知觉的信息加工方式、认知神经机制、跨文化研究以及具有较高生态效度的测量指标等方面进一步探讨.     

我国研究生心理健康研究述评

研究生心理健康目前已逐渐引起人们的关注。本文以近年来我国有关研究生心理健康的研究为依据。对我国研究生心理健康的研究进行了总结与分析，提出了目前研究生心理健康研究的特点与问题，并提出未来研究发展的建议，以期加快我国研究生心理健康的研究步伐。     

由能知而自知--意识研究的若干问题

笛卡尔的“心身二元论”开启了近代以来的心智哲学,他提出的心身问题的两个方面,即心身区别和心身因果相互作用,似乎构成了迄今为止笛卡尔哲学的辩护者和反对者的共同领域。笛卡尔给他的后继者们留下两种可能性:或者是消解二元对立;或者是修订相互作用论,其后世的心智哲学基本上是沿着这两条道路前进的。而当代心智哲学对意识的分析也具体体现了现代哲学对于传统的作为认识主体的“心灵实体”的解构。一　意识的难解之谜关于意识的研究所面对的是两种不同的对象:一种是从主观的角度用内省方法得到的自己头脑中的“内部现象”,我们据此承认意…     

Tests of statistical hypotheses in the case of unequal or disproportionate numbers of observations in the subclasses

General solutions of the analysis of variance in the case of unequal numbers of observations in the subclasses are presented. If we havek criteria for the classification, there will bek! solutions in making a complete analysis and 2^k–1 answers, bearing different meanings, for the sum of squares between subclasses of each criterion. The sum of squares for the interaction of any order, however, will be identical in different solutions of same problem.     

Factorial design and covariance in the study of individual educational development

This is the report of the application of the principles of factorial design to an investigation of individual educational development. The specific type of factorial design formulated was a 2 × 3 × 3 × 3 arrangement, that is, the effect of sex, grade location, scholastic standing, and individual order, singly and in all possible combinations was studied in relation to educational development as measured by theIowa Tests of Educational Development. An application of the covariance method was introduced which resulted in increased precision of this type of experimental design by significantly reducing experimental error. The two concomitant measures used to increase the sensitiveness of the experiment were initial status of individual development and mental age. Without these statistical controls all main effects and two first-order interactions would have been accepted as significant. With their use only sex (doubtful), scholastic standing, and individual order demonstrated significant effects. The chief beauty of the analysis of variance and covariance as an integral part of a self-contained experiment is demonstrated in the complete single analysis of the data. The statistical utilization of the experimental results has also been developed for purposes of estimation and prediction. The mathematical statistician is being continuously required to develop and analyze experimental designs of increasing complexity since the introduction of the analysis of variance and covariance. The mathematical formulation and solution of the problem of this investigation is carried out. The methods illustrated and explained in this study, and modifications and extensions of them are capable of very wide application. The general principles can be used to various degrees and in a number of ways.For the research grant to finance this study, grateful acknowledgment is given to the Graduate School, the University of Minnesota.     

Treatment of Missing Data: Beyond Ends and Means

The ethical decision making process behind the treatment of missing data has yet to be examined in the research literature in any discipline. The purpose of the current paper is to begin to discuss this decision-making process in view of a Foucauldian framework. The paper suggests how the ethical treatment of missing data should be considered from the adoption of this theoretical framework.     

五省部分地区农民工子女心理健康调查

目的：了解农民工子女的心理现状,以提高其心理健康水平。方法：本研究的被试采用《症状自评量表-SCL90》进行测试。结果：（1）农民工子女心理问题的发生率为18．73％,排在前四位的影响因子是：人际敏感、抑郁、焦虑和偏执。（2）农民工子女的人际敏感、抑郁、焦虑、偏执、强迫和精神病性6因子均分显著高于常模;女生的人际敏感、偏执、敌对、强迫和精神病性5因子均分显著高于男生;非独生子女的强迫、人际敏感、忧郁和精神病性4因子均分显著高于独生子女。（3）“留守子女”的抑郁、焦虑、偏执、强迫和精神病性5因子均分显著高于随父母进城的农民工子女。结论：农民工子女的心理健康总体水平不高,社会应给予高度关注。