Incorporating Uncertainty Into Parallel Analysis for Choosing the Number of Factors via Bayesian Methods

A number of psychometricians have suggested that parallel analysis (PA) tends to yield more accurate results in determining the number of factors in comparison with other statistical methods. Nevertheless, all too often PA can suggest an incorrect number of factors, particularly in statistically unfavorable conditions (e.g., small sample sizes and low factor loadings). Because of this, researchers have recommended using multiple methods to make judgments about the number of factors to extract. Implicit in this recommendation is that, when the number of factors is chosen based on PA, uncertainty nevertheless exists. We propose a Bayesian parallel analysis (B-PA) method to incorporate the uncertainty with decisions about the number of factors. B-PA yields a probability distribution for the various possible numbers of factors. We implement and compare B-PA with a frequentist approach, revised parallel analysis (R-PA), in the contexts of real and simulated data. Results show that B-PA provides relevant information regarding the uncertainty in determining the number of factors, particularly under conditions with small sample sizes, low factor loadings, and less distinguishable factors. Even if the indicated number of factors with the highest probability is incorrect, B-PA can show a sizable probability of retaining the correct number of factors. Interestingly, when the mode of the distribution of the probabilities associated with different numbers of factors was treated as the number of factors to retain, B-PA was somewhat more accurate than R-PA in a majority of the conditions.     

数学开放性问题和平行任务的设计:处理数学学习差异的一种途径

普及教育推行以来,处理课堂中学生的学习差异一直是一个世界性的课题。在数学科,按照数学问题或习题的难度进行分层教学是一贯的做法,期望不同能力的学生逐阶而上。然而,激发学生的数学思考,提供不同学生更多的学习机会,是处理差异化教学的关键。在面对混合能力的大班教学中,运用数学开放问题,结合平行练习任务进行分层教学或是一条有效的处理学生数学学习差异的途径。     

提升大学生英语平行文本检索能力的研究

英语平行文本的阅读和借鉴不仅能在应用翻译领域帮助译者摆脱源语文化的束缚、提升译文的地道性,而且能在大学英语教学中帮助学生评估和提升语言输出质量。然而理想的英语平行文本在网络上的检索并非易事。本文针对如今大学生英语学习中信息素养能力欠缺的现状,从搜索方法、信息筛选、信息加工三个方面进行研究,旨在帮助大学生提高英语平行文本网络检索能力。     

运动补偿图像编码中的并行三步算法

本文提出了一种计算运动图像位移矢量Ｄ的新算法。这种新算法称为并行三步算法，模拟结果表明：这种新算法比现有的同类算法有更好的性能。     

仿生关节3A由度并联机构运动分析

自由度仿生关节并联机构具有结构紧凑、承载能力大和易于实现的特点。对3-DOF（RRS型）仿生关节并联机构进行结构原理设计，建立机构位移方程，设计仿生关节机构的结构参数并对其结论作出分析。     

Forward Position Analysis of 5-DOF Parallel Mechanism

Forward position analysis is one of the importantand difficult issues in the kinematic analysis of paral-lel manipulators and has been extensively investiga-ted[1—3]. Most of the approaches for solving forwardposition problems of parallel manipulators with six de-grees of freedom (6-DOF), the Stewart platform forinstance, can be classified into two categories, i.e.closed-form analytical method using polynomial ap-proach and numerical method using iterative algo-rithm. Although the polynomial…     

荧光PCR基因分析仪的快速并行温度控制

提出一种模仿人工经验的智能升降温控制系统,成功地应用于荧光PCR基因分析仪,同时也给出DS18B20温度传感器的详细用法及程序。     

Exact Computation of Parallel Robot''''s Generalized Inertia Matrix

According to the definition of the new hypothetical states which have obvious physical sig-nificance and are termed as no-gravity static and accelerated states, a method for exact computa-tion of the parallel robot's generalized inertia matrix is presented. Based on the matrix theory, the generalized inertia matrix of the parallel robot can be computed on the assumption that the robot is in these new hypothetical states respectively. The approach is demonstrated by the Delta robot as an example. Based on the principle of the virtual work, the inverse dynamics model of the robot is formulized after the kinematics analysis. Finally, a numerical example is given and the element dis-tribution of the Delta robot's inertia matrix in the workspace is studied. The method has computational advantage of numerical accuracy for the Delta robot and can be parallelized easily.     

电阻电容和弹性系数的数学模型

引进类电阻的概念，定义了类电阻的串联和并联，从而给出了电阻、电容和弹性系数的统一的数学模型．     

面向教学的英汉双语平行语料库的创建及其应用

较之于其它大型的或专门用途的英汉双语平行语料库, 个人构建的面向教学的英汉双语平行语料库在大学英语教学中有着独特的优势, 更适合推广使用。大量例证已经表明, 双语平行语料库在大学英语教学上有着广阔的使用前景和潜在的开发价值。