Sample size planning with the cost constraint for testing superiority and equivalence of two independent groups

The allocation of sufficient participants into different experimental groups for various research purposes under given constraints is an important practical problem faced by researchers. We address the problem of sample size determination between two independent groups for unequal and/or unknown variances when both the power and the differential cost are taken into consideration. We apply the well‐known Welch approximate test to derive various sample size allocation ratios by minimizing the total cost or, equivalently, maximizing the statistical power. Two types of hypotheses including superiority/non‐inferiority and equivalence of two means are each considered in the process of sample size planning. A simulation study is carried out and the proposed method is validated in terms of Type I error rate and statistical power. As a result, the simulation study reveals that the proposed sample size formulas are very satisfactory under various variances and sample size allocation ratios. Finally, a flowchart, tables, and figures of several sample size allocations are presented for practical reference.     

New heterogeneous test statistics for the unbalanced fixed‐effect nested design

When the underlying variances are unknown or/and unequal, using the conventional F test is problematic in the two‐factor hierarchical data structure. Prompted by the approximate test statistics (Welch and Alexander–Govern methods), the authors develop four new heterogeneous test statistics to test factor A and factor B nested within A for the unbalanced fixed‐effect two‐stage nested design under variance heterogeneity. The actual significance levels and statistical power of the test statistics were compared in a simulation study. The results show that the proposed procedures maintain better Type I error rate control and have greater statistical power than those obtained by the conventional F test in various conditions. Therefore, the proposed test statistics are recommended in terms of robustness and easy implementation.     

Disentangling the adult attention-deficit hyperactivity disorder endophenotype: parametric measurement of attention

Attention deficit hyperactivity disorder (ADHD) persists frequently into adulthood. The decomposition of endophenotypes by means of experimental neuro-cognitive assessment has the potential to improve diagnostic assessment, evaluation of treatment response, and disentanglement of genetic and environmental influences. We assessed four parameters of attentional capacity and selectivity derived from simple psychophysical tasks (verbal report of briefly presented letter displays) and based on a "theory of visual attention." These parameters are mathematically independent, quantitative measures, and previous studies have shown that they are highly sensitive for subtle attention deficits. Potential reductions of attentional capacity, that is, of perceptual processing speed and working memory storage capacity, were assessed with a whole report paradigm. Furthermore, possible pathologies of attentional selectivity, that is, selection of task-relevant information and bias in the spatial distribution of attention, were measured with a partial report paradigm. A group of 30 unmedicated adult ADHD patients and a group of 30 demographically matched healthy controls were tested. ADHD patients showed significant reductions of working memory storage capacity of a moderate to large effect size. Perceptual processing speed, task-based, and spatial selection were unaffected. The results imply a working memory deficit as an important source of behavioral impairments. The theory of visual attention parameter working memory storage capacity might constitute a quantifiable and testable endophenotype of ADHD.     

自然主义集合实在论与数学哲学研究范式

In recent 50 years,the debate between mathematical realism and anti-realism has been dominating the mainstream development in the contemporary philosophy of mathematics. Penelope Maddy proposed a naturalistic set theoretic realism in 1990. This project brings the philosophy of mathematics a new research idea,that is,philosophy should attach importance to mathematical practice. This article will critically analyze Maddy's naturalistic set theoretic realism on the basis of research paradigm background belief....     

The Effect of Parental Responsiveness on Differences in Psychological Distress and Delinquency between Singleton and Non-Singleton Chinese Adolescents

We assessed the differences in psychological distress and delinquent participation between singleton and non-singleton Chinese adolescents and the extent to which parental responsiveness (mother’s vs. father’s) might account for such differences. Using survey reports of 1,924 7th and 8th graders from three middle schools in the outskirts of Fuzhou, China, we observed small but significant differences between singleton and non-singleton adolescents. Singletons reported lower levels of psychological distress and delinquent participation than non-singleton adolescents. Furthermore, singletons received higher levels of parental responsiveness, which was inversely related to psychological distress and delinquent participation, respectively. The difference in psychological distress between singletons and non-singletons was completely mediated by both maternal and paternal responsiveness. Paternal responsiveness alone fully mediated the difference in delinquent participation between singleton and non-singleton adolescents. We discussed these results in light of both theoretical literature and empirical implications.     

一致的先前知识对类别学习影响机制探讨

探讨一致的先前知识对类别学习的影响,包括2个实验。被试是112名大学生,分别探讨不同实验任务和不同项目呈现时间引发的机械特征在类别学习中的重要程度和加工程度不同的情况下先前知识对类别学习的影响。结果表明:(1)在实验任务为项目类别归属判断任务时,机械特征重要程度低,主题特征与机械特征在学习上存在竞争关系;在实验任务为项目类别归属及记忆任务时,机械特征重要程度高,主题特征与机械特征在学习上存在促进关系。(2)在限制步速呈现项目时,机械特征加工程度低,主题特征与机械特征在学习上存在竞争关系;而在自定步速呈现项目时,机械特征加工程度高,主题特征与机械特征在学习上不存在竞争关系。     

“物质无限可分”是全称存在命题

运用分析哲学方法研究物质可分性问题,能够得到这样的结果:"物质无限可分"是全称存在命题;"物质有限可分"是存在非存在命题。而这两个命题都既不可证实又不可证伪。因此,"物质结构是否无限可分"是一个超经验的信仰问题,无法从经验上证明究竟是肯定回答正确,还是否定回答正确,因而这方面的争论没有什么意义。     

Has someone moved my plate? The immediate and persistent effects of object location changes on gaze allocation during natural scene viewing

In this study, we investigated the immediate and persisting effects of object location changes on gaze control during scene viewing. Participants repeatedly inspected a randomized set of naturalistic scenes for later questioning. On the seventh presentation, an object was shown at a new location, whereas the change was reversed for all subsequent presentations of the scene. We tested whether deviations from stored scene representations would modify eye movements to the changed regions and whether these effects would persist. We found that changed objects were looked at longer and more often, regardless of change reportability. These effects were most pronounced immediately after the change occurred and quickly leveled off once a scene remained unchanged. However, participants continued to perform short validation checks to changed scene regions, which implies a persistent modulation of eye movement control beyond the occurrence of object location changes.     

显示方式对小学生阅读动态文本的影响

以小学三年级和五年级学生为被试,在机控速度（240字/分）条件下,如何在单行呈现动态文本以提高小学生的阅读绩效。实验采用2（呈现方式：引导式、RSVP）×2（年级：三年级、五年级）×2（窗口：5字、10字）的多因素混合实验设计。结果发现：（1）在呈现方式上,平滑滚动引导式优于RSVP,更受被试偏爱;（2）在两种呈现方式下,五年级的阅读正确率显著高于三年级;（3）与平滑滚动引导式相比,窗口大小对RSVP的影响更大。     

一种对动物学习记忆能力突变筛查的新途

本文详细描述了一种全自动化的行为检测方案。在自然饲养环境/检测环境(24/7)中, 我们测量了小鼠针对两个给食器中获得食物的比例与它们在相应给食器停留时长的比例进行匹配的精确性与准确性。该方案是对传统条件性习得 (trials-to-acquisition) 行为测验设备的改进, 可以检测动物时间间隔能力的精确性与准确性, 对定时目标选择的相关概率的效果, 以及记忆一天中从不同给食器中获得食物次数的精确性与准确性。该压缩系统避免了在整个实验过程中对小鼠的持握操作, 可忽略实验者/技术员的实验操作时间, 而且可以递送小鼠置入实验环境后, 7~9个实验日中全部3组实验流程产生的大量结果。其中, 第一个实验流程为单个24小时周期内完成的时间匹配能力的筛查, 它对动物的时间、空间估计能力的记忆机制进行精确检测。因此, 该系统允许在有限的实验空间、较短的实验周期内, 对大量的实验小鼠进行有可能存在的学习记忆能力缺陷进行大规模筛查。此外, 该系统运行所依赖的软件可以在公共开放平台获得。