题库建设中试题难度的修订和校准

针对两种测量理论(CTT和IRT)统计结果之间存在的相关性,提出在题库建设中试题难度参数确定上,以IRT在试题参数测试的不变性为基础,充分利用CTT的优点,取两者之所长,将两者有机地融合,使确定的难度系数具有客观性和科学性.     

2PL模型的EM缺失数据处理方法研究

项目反应理论(IRT)模型是教育统计与测量中一种十分重要的模型,它包含项目参数和能力参数.目前一种常用的估计IRT模型项目参数的方法是由Woodruff和Hanson(1997)应用EM算法给出的,它用于完全反应数据,而把能力参数看作缺失数据.本文将Woodruff的方法推广到处理缺失反应的情况,基本思想是把能力参数和缺失反应均看作缺失数据,再运用EM算法估计参数.通过模拟研究,在不同被试人数和不同缺失比例的情况下,本文比较了我们给出的方法和BILOG-MG软件的缺失数据处理方法的参数估计效果.结果表明,在大多数情况下,本文提出的方法能得到更好的估计.     

基于GPCM的高中数学教师评价指标体系的调查与分析

为突出教师本人在评价中的主体地位,改变传统的至上而下的评价方式,针对高中数学教师评价指标体系设计问卷进行调查,运用项目反应理论(IRT)中的拓广分部评分模型(GPCM),应用Parscale统计软件对问卷调查结果进行统计分析,获得对高中数学教师评价指标体系的认同度.     

金融风险管理中VaR度量的光滑估计效率

本文研究了金融风险管理理论中风险价值(VaR)的非参数核光滑估计和经验估计的效率问题.对非独立的时间序列损失/收益样本,在均方误差(MSE)准则的意义下引入亏量的概念,亏量越大表明估计效率越低.并利用亏量对VaR模型的核光滑估计和基于样本分位数的经验估计进行了比较,在理论上证明了VaR模型的核光滑估计优于经验估计.同时,通过计算机模拟证实了理论获得的结论.本文还对国内沪深两市上的证券投资基金进行了实证分析,计算了样本基金的VaR风险度量的经验估计和核光滑估计,并计算了样本基金基于周收益率和VaR估计的风险调整收益(RAROC)值,以此对样本基金的业绩做出了有用的评价.     

试卷水平的标准化定量评价

通过建立一个实用标准化评价模型,根据转换参数(偏移参数和膨胀参数)给出试卷水平的标准化评价,并对其做Kappa一致性检验.Kappa系数K作为试卷水平系数.X~2一致性检验和理想模式比较检验从不同角度验证了标准化评价的有效性.给出了两个样本组的实证分析.     

基于风险分析的商业银行项目贷款评估改进研究

项目贷款评估是商业银行风险防范的重要环节,对商业银行资产质量起着至关重要的作用.以项目评估理论为基础,对商业银行项目贷款评估存在的问题进行剖析,对影响项目贷款还款能力的关键风险因素进行分类和细化,以风险为导向重构项目贷款评估指标体系,建立评价指标的评语集和隶属度,设置了项目贷款评估标准,基于模糊综合评价对贷款项目进行定量评价和等级划分,最后选取实际项目进行实证研究,为商业银行项目贷款的科学决策和合理投放提供依据.     

适用于二级与多级评分项目组成的混合测试的加权最大似然潜在特质估计（英文）

提出适用于二级与多级评分项目组成的混合测试的加权最大似然潜在特质估计.使用N-R算法获得WML估计,并给出相关方程的详细推导.为探讨WML的性能,进行了模拟研究,所得到的结果表明,WML的估计比最大似然估计（MLE）具有更好的性能.最后,基于一个实际例子对该方法进行了实证研究.     

节能项目经济性评价的灰面积关联模型

为完善节能项目评价及管理的决策支持,建立基于灰面积关联决策的节能项目评价模型.以灰色关联决策理论为基础,分析经典灰色关联决策方法的优缺点,采用被选方案与理想方案间两曲线相邻点间多边形面积作为关联系数,度量曲线的几何形状的相似性,构建了灰色关联度公式.采用某企业计划发展的节能项目数据为实证样本,根据其成本、能耗数据及六项指标对节能项目进行评价,分析节能项目方案间的差异.通过算例验证了灰面积关联决策模型的合理性和算法的有效性,为节能项目评价及管理提供新的决策模型.     

基于价值工程的房地产项目管理应用研究

房地产项目投资巨大,过程繁多,而房地产项目管理的方法和水平如何直接影响到房地产企业效益的高低.因此,通过对房地产项目全过程的分析,提出了房地产项目全过程功能指标体系,并结合价值工程理论提出了房地产项目全过程运用价值工程的思想,通过运用三家房地产公司房地产项目的成本数据进行实证分析,验证了指标体系和房地产全过程价值工程理论的合理性,为房地产企业全过程运用价值工程理论提供了指导.     

基于EFCE的创新方法集成应用的评价与实证分析——以中航工业集团创新方法应用为例

通过广泛征求工程技术项目专家、管理者、技术研发人员的意见,构建了4维度12个指标的工程技术项目创新方法集成应用评价的指标体系,运用熵权模糊综合评判法(EFCE)对创新方法在工程技术项目中的集成应用水平进行评价.以中航工业航天工程项目研发团队为例进行实证调研分析,得出了创新方法集成应用的程度评价,并给出解决问题的方向.     

制造企业服务化绩效评价指标体系研究

采用扎根理论方法建立指标全集,通过指标重要性分析、相关性分析以及信效度检验“三层筛选”,设计制造企业服务化绩效评价指标体系。研究结果表明,制造企业服务化绩效由产品绩效、顾客绩效、财务绩效和市场绩效4个维度构成,指标体系涵盖12个二级指标,具有较好的信度和效度。研究结论为企业评价和相关实证研究提供了理论依据。     

Application of robust optimization to automated test assembly

In automated test assembly (ATA), 0-1 linear programming (0-1 LP) methods are applied to select questions (items) from an item bank to assemble an optimal test. The objective in this 0-1 LP optimization problem is to assemble a test that measures, in as precise a way as possible, the ability of candidates. Item response theory (IRT) is commonly applied to model the relationship between the responses of candidates and their ability level. Parameters that describe the characteristics of each item, such as difficulty level and the extent to which an item differentiates between more and less able test takers (discrimination) are estimated in the application of the IRT model. Unfortunately, since all parameters in IRT models have to be estimated, they do have a level of uncertainty to them. Some of the other parameters in the test assembly model, such as average response times, have been estimated with uncertainty as well. General 0-1 LP methods do not take this uncertainty into account, and overestimate the predicted level of measurement precision. In this paper, alternative robust optimization methods are applied. It is demonstrated how the Bertsimas and Sim method can be applied to take this uncertainty into account in ATA. The impact of applying this method is illustrated in two numerical examples. Implications are discussed, and some directions for future research are presented.     

Birmbaum信息与多个测验分数的最佳组合法

本文用现代教育、心理测量的ＩＲＴ（项目反应理论）中的Ｂｉｒｍｂａｕｍ信息函数，对经典教育、心理测量（ＣＴＴ）中的真实分数模型Ｘ＝Ｔ＋ｅ给出了一种多个测量分数的最佳组合法。该组合获得最大信息，并突破了ＩＲＴ和ＣＴＴ的局限性。     

实施院内分级教学 全面提高教学质量——《高等数学》课程实施分级教学的理论与实践

分级教学是基于素质教育理念下的一种全新的教学模式,也是一种面向全体、注重差异、因材施教的一种教学策略,它具有差异性、层次性、针对性、实效性和发展性等五大特征;依据教育教学理论与实践,分级教学要求大纲分级、目标分级、学生分级、授课分级、作业分级、辅导分级、考核分级和评价分级.二年来,我院《高等数学》课程实施了院内分级教学,由于措施得力,方法得当,初见成效,取得了一些可资借鉴的宝贵经验.     

The Generalised Pro-Fitting Subgroup of a Profinite Group

The generalised Fitting subgroup of a finite group is the group generated by all subnormal subgroups that are either nilpotent or quasisimple. The importance of this subgroup in finite group theory stems from the fact that it always contains its own centraliser, so that any finite group is an abelian extension of a group of automorphisms of its generalised Fitting subgroup. We define a class of profinite groups which generalises this phenomenon, and explore some consequences for the structure of profinite groups.     

Examination-Type Preferences of College Science Students and Their Faculty in Israel and USA: A Comparative Study

The science-examination preferences of college science students and their science faculty were surveyed, using the TOPE questionnaire at a teacher training and a community college in Israel and the U.S., respectively. The results obtained in the two countries were “intrally” and “interly” compared, in total and by gender, in terms of significant/no significant differences in the preferences made and the reasons provided by the students and faculty for their ranking. The findings suggest that: (a) college science students prefer mostly, the Israelis more so than the Americans, the nonconventional, written exams in which time is unlimited and any materials are allowed; (b) American college science students prefer the traditional class science examination (G) significantly more than their Israeli counterparts; (c) the preference of higher order cognitive skills (HOCS)-oriented exams (B. I and H) is significantly higher for female science students in Israel compared with no gender difference concerning the preferred examinations in the US, and rejection of oral examinations by all in both countries, significantly more by female students; and (d) there exists a significant gap between the preferred type of examinations of science students and their faculty in both countries. In view of the HOCS-orientation and the goal of conceptual understanding in current reforms of science education worldwide, the consonance between these curriculum objectives and examination practices is advocated. This, in turn, requires that provisions be made to lessen the gap between science teachers and their students' examination type preferences for better science learning to occur.     

关于极限理论的学习经验

分析极限理论在数学分析学习中的重要性，介绍学习极限理论的三点经验与体会，即充分理解基本内容；加强基本功训练；试着多问自己一些问题，学会举出各种各样的例子。     

A Look at Examinations

This paper discusses various aspects of mathematics examinations and gives the results of some experiments which highlight the discrepancies that arise between the marks obtained in two equivalent mathematics examination papers.     

Convergence in Conformal Field Theory

Convergence and analytic extension are of fundamental importance in the mathematical construction and study of conformal field theory. The author reviews some main convergence results, conjectures and problems in the construction and study of conformal field theories using the representation theory of vertex operator algebras. He also reviews the related analytic extension results, conjectures and problems. He discusses the convergence and analytic extensions of products of intertwining operators (chiral conformal fields) and of q-traces and pseudo-q-traces of products of intertwining operators. He also discusses the convergence results related to the sewing operation and the determinant line bundle and a higher-genus convergence result. He then explains conjectures and problems on the convergence and analytic extensions in orbifold conformal field theory and in the cohomology theory of vertex operator algebras.     

数论及其应用 献给陈省身先生九十大寿

众所周知 ,数论是数学中最古老最纯粹最优美的一个学科 .不过鲜为人知的还是 ,数论同时也是一门应用性极强的应用数学学科 .著名国际数学大师陈省身教授早在 1 992年精辟地指出 :“数学中我愿意把数论看作应用数学”,“我想数学中有两个很重要的数学部门 ,一个是数论 ,另一个是理论物理”.在本文中 ,我们将先扼要介绍一下数论中的一些基本概念、几个主要难题 ,紧接着我们要介绍数论 (尤其是数论中的难题 )在现代密码学 (包括网络与信息安全 )与计算机科学 (尤其是快速并行计算 )中的应用