Evaluation of treatment effect estimates in single‐case experimental research: comparison of twelve overlap methods and visual analysis

The purpose of this study was to compare 12 commonly‐used nonoverlap methods with each other and with the results of visual analysis. Data were obtained from 25 studies focused on embedded instruction and schema‐based instruction and included a total of 101 graphs. Treatment effect estimates using 12 nonoverlap methods were calculated for each graph by hand or using an online calculator. Five experts conducted visual analysis of each graph. Results showed that strong agreements existed between visual analysis and PND, Tau_NOVLAP and Tau‐U when raw data were analysed, and PND, PNCD and PEM‐T when categorised data were analysed. Of the 12 methods investigated, PND had the highest agreement rate with visual analysis, followed by PEM‐T, PAND, PNCD, IRD, NAP and Tau_NOVLAP. Overall, visual analysis appeared to be more conservative, as most nonoverlap methods overestimated the treatment effect. Additional research is needed to replicate and potentially validate the findings of this study.     

Evaluating population estimates in the United States: Counting the population between the censuses

Population estimates play an important role in shaping public policy and research. Librarians as well as users need to be proficient in evaluating the limitations of the statistic. This article provides a brief history of population estimates as well as a discussion of general principles for evaluating and understanding population estimates.     

扭摆法测转动惯量的研究

本文探讨了利用扭摆法测量转动惯量的误差来源,并通过实际测量,指出了减少实验误差的方法。     

预应力索杆结构的施工张力偏差分析

本文基于索长误差的概率分布模型,分析预应力索杆结构施工张拉的初始预应力偏差。首先讨论了索长误差的随机数学模型,建立了一种关于预应力索杆结构索长误差效应的计算方法。其次以实际工程为算例,考察不同的索长误差对结构初始预应力的影响,并比较不同的施工张拉方案对于减小索长误差影响的效果。分析结果表明,合理的张拉方案能有效减小结构的初始张力偏差。     

基于线性逼近的555压控振荡器特性分析

由555时基电路构成的压控振荡器,通过改变控制电压Vco可调节输出方波的占空比q,由于二者成非线性关系,给实际应用带来不便。文章对555压控振荡器的q-Vco曲线进行了线性最佳一致逼近,并结合数据对误差进行了分析。     

The Mathematics of Estimation: Possibilities for Interdisciplinary Pedagogy and Social Consciousness

The purpose of this article is to report on the importance of providing pre-service and in-service teachers with experience and specific training in critical thinking skills. The essential concepts in elementary mathematics curricula can be augmented to include and cultivate critical thinking skills that have tremendous ramifications for future leaders and for those who move on to more technical training. A sample problem, along with pre-service teacher responses, is used here to show the necessity and importance of this kind of training as the responses show clear evidence of a certain naivete on the part of these college level students. The responses do show evidence of budding social conscience in the students, but the level of expertise in critical thinking is not at all sophisticated. We discuss and explore the implications of our approach.     

The role of teacher’s corrective feedback in improving Iranian EFL learners’ writing accuracy over time: is learner’s mother tongue relevant?

The purpose of the present study was to investigate the impact of feedback on writing accuracy over time and examine the relevance of the students’ mother tongue to the feedback effect. To this end, the study compared two groups of Iranian English majors (N = 56) over a period of four months: one with indirect grammar feedback and the other with no grammar feedback whatsoever. The results of the study did not show a significant effect for the teachers’ feedback. However, the results showed a main effect for practice and the interaction of practice and feedback as a result of which both groups improved their writing accuracy over the course of one semester, with the feedback group making more improvement. The results also showed significant differences between the two groups in reducing their errors in various grammatical categories. The study further revealed that the success ratio of error reduction in each category was highly sensitive to cross-linguistic differences. The students’ views, elicited after the study, support the findings obtained from the analysis of the quantitative data.     

异质面板视角下人力资本与节水潜力的协整关系研究

运用面板计量分析方法,研究了中国各区域人力资本与节水潜力之间的关系。实证研究发现大部分地区的人力资本与节水潜力间存在不同程度的Granger因果关系。受教育程度、技术进步等因素对节水潜力的影响,也呈现出明显的地区异质性。此外,部分地区不存在短期关系,说明其人力资本和节水潜力变化只有在基于长期判断时才有价值;人力资本与节水潜力之间的关系不受地区经济发展水平的影响,说明从此视角制定的节水政策具有普适性。     

膜振动一致椭圆型问题的加权特征值上界估计

考虑膜振动一致椭圆型问题的加权特征值上界估计,利用试验函数、分部积分法、Rayleigh定理以及不等式估计等方法,建立了用前n个特征值来估计第n＋1个特征值的上界估计,其估计系数与区域度量无关．这个结果在力学和物理学中有着广泛的应用．     

浅析中文文献主题标引的准确性

本文分析探讨了图书主题标引误差的表现形式及产生的原因，并提出了预防和减少此类标引问题的建议和设想。参考文献3。