幼儿在集合比较中运用数数的实验研究

本研究中运用了两个实验探讨数数干预和测查条件对儿童在集合比较中运用数数的影响。干预对3岁儿童(M=3：9)没有影响。在平均年龄为4岁4个月时．干预组儿童比控制组儿童更倾向于用数数比较集合．自然组儿童也比传统组更倾向于用数数。许多4岁儿童在无干预时不用数数可能是因为,1)不知数数比视觉性比较更有效,或2)他们在集合比较中的数数极易受测查情景因素的影响。儿童在集合比较中的数数运用与他们的数数水平密切关联。     

问题解决中策略的变化：一项微观发生研究

以30名小学三年级儿童为被试,以一种特殊的方程问题为材料,采用微观发生法,先后进行了5次测查,收集了解题后的口语报告资料,从策略变化的路线、速率、广度、来源以及变化模式的多样性等方面详细探讨了问题解决策略的变化过程。结果发现,在面临新的问题时,被试缺乏相应知识和专门的解题策略,这时以使用多种常规策略以及错误策略为主;此后,当被试建构起对问题的正确表征时,就以使用正确策略为主,甚至发现了非常有技巧性和领域专门性的快捷策略,这时策略的数量明显减少;在面临难度较大的迁移题目时,快捷策略的使用率又降低,而更多借助于常规策略。可见,策略的获得是一个由错误到正确、由多种尝试到选择其一、由一般到专门的演化过程,这主要是一个学生自主建构的过程,当然也受到正式和非正式教育提供的知识的影响。值得说明的是,快捷策略的获得受到问题呈现模式的影响。总是呈现相同题目的单一模式有助于快捷策略的发现,而在混合训练中,插入不同性质的题目会干扰快捷策略的发现;但是,当面临迁移问题时,单一训练相比于混合训练的优势会消失。此外,正确使用常规策略是发现快捷策略的前提。     

The influence of satisfaction and promotability on the relation between career adaptability and turnover intentions

This study examined the relation between career adaptability (CA), promotability, and career satisfaction (CS), and their impacts on turnover intentions (TI). Eight hypotheses were proposed. Based on data collected from a sample of 431 employees in Macau, career adaptability was significantly and positively related to both promotability and CS after controlling for the influences of demographic variables including age, gender, education and tenure. CA, promotability and CS were also significantly and negatively linked to TI. The results further revealed that promotability and CS mediated the effect of CA on TI. The study contributed new insights that may inform career development and retention of employees. Practical implications on how to retain employees were discussed.     

Conflict Minerals in Electronic Systems: An Overview and Critique of Legal Initiatives

The Democratic Republic of Congo has vast natural resources, many of which are regularly exploited by the electronics industry. Unfortunately, in addition to these resources, there are widespread human rights abuses committed by armed groups entrenched in the eastern part of the Democratic Republic of Congo. These armed groups are using profits from these minerals as a source of funding. Their human rights abuses have led to a growing humanitarian interest in the region and prompted the international community to action. This paper explores the conflicts in the Democratic Republic of Congo, provides an understanding of the link between human rights abuses and conflict minerals, and interprets and critiques the legal actions of the international community.     

The Underlying Role of Negative Affect in the Association between PTSD,Major Depressive Disorder,and Generalized Anxiety Disorder

Clinicians and researchers have found differential diagnosis to be difficult, particularly for conceptually similar disorders. One category of particular interest has been distress or internalizing disorders, theorized to be related via an underlying construct of generalized distress or negative affect. The present study attempted to address the comorbidity of three distress disorders - posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) - using latent analyses by controlling for the variance attributable to negative affect. The sample consisted of 265 trauma-exposed individuals who completed self-report measures of PTSD, MDD, GAD, and negative affect. Confirmatory factor analysis was used to test initial model fit. Next, the model was re-computed, controlling for negative affect by regressing negative affectivity at the item-level. Results indicated that a significant amount of variance within and between these diagnostic categories is attributable to negative affect at both the item- and factor-level. The hypothesis that MDD’s non-somatic/affective factor and the GAD factor would have the highest attenuations in factor loadings after controlling for negative affect was supported. Therefore, negative affect significantly influences the co-occurrence of PTSD, MDD, and GAD clinically, emphasizing the need for transdiagnostic interventions for trauma victims.     

The role of retrieval mode and retrieval orientation in retrieval practice: insights from comparing recognition memory testing formats and restudying

The effectiveness of retrieval practice for aiding long-term memory, referred to as the testing effect, has been widely demonstrated. However, the specific neurocognitive mechanisms underlying this phenomenon remain unclear. In the present study, we sought to explore the role of pre-retrieval processes at initial testing on later recognition performance by using event-related potentials (ERPs). Subjects studied two lists of words (Chinese characters) and then performed a recognition task or a source memory task, or restudied the word lists. At the end of the experiment, subjects received a final recognition test based on the remember–know paradigm. Behaviorally, initial testing (active retrieval) enhanced memory retention relative to restudying (passive retrieval). The retrieval mode at initial testing was indexed by more positive-going ERPs for unstudied items in the active-retrieval tasks than in passive retrieval from 300 to 900 ms. Follow-up analyses showed that the magnitude of the early ERP retrieval mode effect (300–500 ms) was predictive of the behavioral testing effect later on. In addition, the ERPs for correctly rejected new items during initial testing differed between the two active-retrieval tasks from 500 to 900 ms, and this ERP retrieval orientation effect predicted differential behavioral testing gains between the two active-retrieval conditions. Our findings confirm that initial testing promotes later retrieval relative to restudying, and they further suggest that adopting pre-retrieval processing in the forms of retrieval mode and retrieval orientation might contribute to these memory enhancements.     

The centroid paradigm: Quantifying feature-based attention in terms of attention filters

This paper elaborates a recent conceptualization of feature-based attention in terms of attention filters (Drew et al., Journal of Vision, 10(10:20), 1–16, 2010) into a general purpose centroid-estimation paradigm for studying feature-based attention. An attention filter is a brain process, initiated by a participant in the context of a task requiring feature-based attention, which operates broadly across space to modulate the relative effectiveness with which different features in the retinal input influence performance. This paper describes an empirical method for quantitatively measuring attention filters. The method uses a “statistical summary representation” (SSR) task in which the participant strives to mouse-click the centroid of a briefly flashed cloud composed of items of different types (e.g., dots of different luminances or sizes), weighting some types of items more strongly than others. In different attention conditions, the target weights for different item types in the centroid task are varied. The actual weights exerted on the participant’s responses by different item types in any given attention condition are derived by simple linear regression. Because, on each trial, the centroid paradigm obtains information about the relative effectiveness of all the features in the display, both target and distractor features, and because the participant’s response is a continuous variable in each of two dimensions (versus a simple binary choice as in most previous paradigms), it is remarkably powerful. The number of trials required to estimate an attention filter is an order of magnitude fewer than the number required to investigate much simpler concepts in typical psychophysical attention paradigms.     

Image-processing algorithms for behavior analysis of group-housed pigs

Computational algorithms of image processing were developed and evaluated to select, by motion detection, images of resting artificial pigs and to segment the pigs (mixture of black and white pigs) from their background. Motion detection of the pigs was implemented by detecting interframe differences of postural behavioral images. This algorithm combines the advantages of likelihood ratio method and shading model method and shows a stable performance under noisy and dynamic illumination conditions. Segmentation of the pigs from their background was implemented by employing multilevel thresholding and background reference techniques. The algorithm automatically determines the number of thresholds needed and produces satisfactory segmentation when both black and white pigs with different image intensities are present at the same time (the most complicated situation). The reference background image is updated so that temporal changes in illumination and/or spatial changes of the pen condition have little effect on the performance of image segmentation. The algorithm employs statistical models of the pigs and background and Bayes hypothesis testing to obtain and update the exposed portion of the reference background. Linear filters were used in this process for updating the parameters. These algorithms will serve as essential components for a novel, behavior-based, interactive approach to assess and control thermal comfort of group-housed pigs, which is expected to result in enhanced animal health and well-being.