Sensitivity of Fit Indices to Misspecification in Growth Curve Models

This study investigated the sensitivity of fit indices to model misspecification in within-individual covariance structure, between-individual covariance structure, and marginal mean structure in growth curve models. Five commonly used fit indices were examined, including the likelihood ratio test statistic, root mean square error of approximation, standardized root mean square residual, comparative fit index, and Tucker-Lewis Index. The fit indices were found to have differential sensitivity to different types of misspecification in either the mean or covariance structures with severity of misspecification controlled. No fit index was always more (or less) sensitive to misspecification in the marginal mean structure relative to those in the covariance structure. Specifying the covariance structure to be saturated can substantially improve the sensitivity of fit indices to misspecification in the marginal mean structure; this result might help identify the sources of specification error in a growth curve model. An empirical example of children's growth in math achievement (Wu, West, &; Hughes, 2008 Wu, W., West, S. G. and Hughes, J. N. 2008. Effect of retention in first grade on children's achievement trajectories over four years: A piecewise growth analysis using propensity score matching.. Journal of Educational Psychology, 100: 727–740. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) was used to illustrate the results.     

不同线索下特质焦虑个体的返回抑制

焦虑与注意偏向的研究是近年来情绪与认知领域的热点。为探讨特质焦虑个体的注意偏向特点及其返回抑制能力是否受不同线索的调节, 采用特质焦虑量表筛选高特质焦虑大学生29名, 低特质焦虑大学生28名完成线索-靶子任务。要求被试在提示线索消失后, 对位置进行快而准地辨别反应, 分别探索中性和情绪性提示线索下被试的返回抑制。结果发现：(1)在中性线索条件下, 高焦虑个体平均反应时慢于低焦虑个体。(2) 在情绪线索条件下, 高焦虑个体在负性线索下的反应时小于在正性线索下的反应时; 高、低焦虑个体在各种SOA条件下均出现了返回抑制, 但各组返回抑制量受到情绪线索的调节：在正性情绪线索条件下, 两组返回抑制量没有显著差异; 在负性情绪线索下, 高焦虑个体返回抑制量显著小于低焦虑个体。这表明, (1)焦虑个体的注意偏向受到刺激信息的影响：只对负性情绪线索出现注意警觉; (2)只有在涉及负性情绪信息时高、低焦虑个体返回抑制能力才有差异, 高焦虑个体存在对负性情绪线索的抑制困难。     

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.     

Long-term memory of hierarchical relationships in free-living greylag geese

Animals may memorise spatial and social information for many months and even years. Here, we investigated long-term memory of hierarchically ordered relationships, where the position of a reward depended on the relationship of a stimulus relative to other stimuli in the hierarchy. Seventeen greylag geese (Anser anser) had been trained on discriminations between successive pairs of five or seven implicitly ordered colours, where the higher ranking colour in each pair was rewarded. Geese were re-tested on the task 2, 6 and 12 months after learning the dyadic colour relationships. They chose the correct colour above chance at all three points in time, whereby performance was better in colour pairs at the beginning or end of the colour series. Nonetheless, they also performed above chance on internal colour pairs, which is indicative of long-term memory for quantitative differences in associative strength and/or for relational information. There were no indications for a decline in performance over time, indicating that geese may remember dyadic relationships for at least 6 months and probably well over 1 year. Furthermore, performance in the memory task was unrelated to the individuals’ sex and their performance while initially learning the dyadic colour relationships. We discuss possible functions of this long-term memory in the social domain.     

Need Satisfaction Supportive Game Features as Motivational Determinants: An Experimental Study of a Self-Determination Theory Guided Exergame

Empirical studies have validated that basic needs satisfaction supported by video game play predicts motivation and engagement outcomes. However, few studies specifically manipulated game features for each of the three basic needs specified in the self-determination theory (SDT) to examine how the game features impact players' need satisfaction and game experience. The current study employed an in-house developed exergame and manipulated the game features in a 2 (autonomy-supportive game features: on vs. off) × 2 (competence-supportive game features: on vs. off) experiment to predict need satisfaction, game enjoyment, motivation for future play, effort for gameplay, self-efficacy for exercise using the game, likelihood of game recommendation, and game rating. The manipulated game features led to the corresponding need satisfaction. Manipulated autonomy-supportive and competence-supportive game features had main effects on most motivation and engagement outcomes. Need satisfaction of autonomy and need satisfaction of competence were both found to be mediators for the relationships between the game features and the motivation and engagement outcomes. The findings add evidence to support the underlying mechanism postulated by SDT for media enjoyment and motivation as well as the emerging entertainment research conceptualizing enjoyment as need satisfaction. The findings also have practical implications for intervention effort that intends to capitalize the motivational pull of video games.     

The Third-Person Effects of Political Attack Ads in the 2004 U.S. Presidential Election

This study examines the indirect effects of extensive negative political attack ads in the 2004 presidential election from a third-person effects perspective. Results of a survey using a probability sample of 496 college students indicate that these students believe attack ads harm others more than themselves. Moreover, the respondents tended to perceive attack ads in traditional media to have a greater harmful effect on self and others than attack ads on the Internet. Contingent factors that account for the magnitude of third-person effects include social distance and knowledge. Further, exposure to attack ads was found to be the strongest predictor of perceived harms of such ads on self and others, but only perceived harm on others is a significant predictor of support for restrictions on attack ads. The study contributes to research on the third-person effect by testing perceived harms of attack ads on self and others separately on likelihood to support restrictions.     

音乐对工作记忆影响及机制的ERP研究

以肖邦音乐为刺激材料,采用数字n-back实验范式来研究肖邦音乐对工作记忆的影响方式,并通过运用事件相关电位技术(ERP技术),研究不同音乐条件下,正常人大脑皮层的脑电活动情况,进而探讨音乐对工作记忆影响的神经机制。30名被试参加了3种音乐条件(无音乐、先导音乐、背景音乐)下的n-back(n=1、2)工作记忆任务的行为实验,收集行为数据;14名被试参加了同样实验过程的ERP实验,记录脑电数据。行为结果发现音乐条件对工作记忆效果有显著影响,且先导音乐条件下记忆效果最好;脑电结果显示P3波幅随记忆负荷的增加呈下降趋势,高记忆负荷水平下,P3波幅随先导音乐、背景音乐、无音乐的顺序逐渐呈现下降趋势;源定位分析发现音乐对工作记忆的促进作用可能跟大脑顶叶被激活有关。     

选择反应作业中的反应组织

通过2-选择反应作业的两个反应复杂度不对称（不等）实验因素考察反应组织,发现在同一作业中无反应复杂度效应,而作业之间反应复杂度效应显著。这提示选择反应是选择已完成组织的反应,而不是实时地进行反应动作组织,进而引入动作模块的概念。即把反应组织视为选择动作模块过程。其实际意义是,在操作界面的优化设计中,要提高一组同时可选择操作R中的某一种操作Ri(R∈Ri|i=1,2,…,n）的绩效,其有效途径是应降低这一组操作R的平均复杂度;如果只降低Ri的复杂度,要提高其绩效收效甚微。     

文本结构和时间应激对网页阅读绩效的影响

探讨了文本结构和时间应激对网页阅读绩效的影响效应。采用 2× 3被试间设计 ,自变量为文本结构和阅读时间 ,因变量为找到相关信息的时间及途径的额外节点数。结果发现 ,主效应及交互作用的影响均十分显著。其中 ,当阅读时间为 10和 2 0min时 ,超文本阅读的绩效均显著低于线性文本 ,而在 30min时两者无显著差异 ;对超文本 ,三种阅读时间的效应存在显著差异 ,而对线性材料 ,阅读时间的效应无显著差异。结论 :时间应激对超文本阅读绩效的影响更为明显