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1.
在多项选择题测验分数等于真实分数和猜测分数之和的假设模型下,本文得到了一个多项选择题测验信度的理论公式,并由此给出了测验信度的估计方法。最后,通过两个例子,说明了本文提出的方法在测验信度分析中的应用,并将这种方法与教育测量中常用的库德——理查逊方法(Kuder-Richardson)进行了比较  相似文献   

2.
ONTHECLASSφ_p~*(α,β,γ,ε,η;A)ofp-VALENTFUNCTIONSWITHREFERENCETOTHEBERNARDIINTEGRALOPERATORJianMing(蹇明)(WuhanUniversity,Wuhan430...  相似文献   

3.
设(T,Σ,u)是有限测定空间,表示定义在T上取值于X的p幂Bochner可积函数空间。本文主要证明了Lp(T,X)中的一般子集G和Lp(T,Y)型子集为太阳集的特征定理;对实Hibert空间X,得到了子集Lp(T,Y)为Lp(T,X)的半Chebyshev太阳集的特征,同时给出了子集Lp(N,Y)是Lp(N,X)的强Chebyshev子空间的条件。  相似文献   

4.
数学教育中的问题解决及其教学途径   总被引:1,自引:0,他引:1  
数学教育中的问题解决及其教学途径李友国(华东师大数学系研究生200062)自1980年全美数学教师协会(NCTM)发文正式提出“问题解决应是学校数学教学的一个焦点”以来,数学教育中的问题解决已越来越受到人们的青睐和重视,目前已成为世界性的数学教学的口...  相似文献   

5.
中立型时滞模型的周期正解   总被引:18,自引:0,他引:18  
李永昆 《数学学报》1996,39(6):789-795
本文通过使用某些新技巧,研究了中立型时滞模型N'(t)=N(t)[a(t)--β(t)-b(t)N(t-T(t))-C(t)N'(t-T(t))]周期正解的存在性,解决了文[1]中的一个公开问题,并改正了文[2]中的错误。  相似文献   

6.
涂生 《应用数学学报》1994,17(3):393-400
多项式模与线性系统(Ⅱ):状态反馈与结构形式涂生(南开大学数学系,天津300071)POLYNOMIALMODULESANDLINEARSYSTEMS(Ⅱ):STATEFEEDBACKANDSTRUCTURALFORMS¥TUFENGSHENG(De...  相似文献   

7.
MEANVALUEOFANALYTICOPERATORFUNCTIONSYuXiaopei(喻小培)(Dept.ofMath.,CentralChinaNormalUniversity,Wuhan430070,China)JianMing(蹇明)(D...  相似文献   

8.
GLOBAL ATTRACTIVITY IN A PERIODIC COMPETITION SYSTEM WITH FEEDBACK CONTROLS   总被引:5,自引:0,他引:5  
WENGPEIXUAN(翁佩萱)(DepartmentofMathematics,SouthChinaNormalUniversity,Guangzhou510631,China)GLOBALATTRACTIVITYINAPERIODICCOMPET...  相似文献   

9.
ANOTEONVECTORVALUEDANALYTICFUNCTIONS¥ZHANGHAITAO(DepartmentofMathematics,ZhejiangUniversity,Hangzhou310027)Abstract:Analyticf...  相似文献   

10.
C-COSINEOPERATORFUNCTIONS¥HuangTingwen(黄廷文)&HuangFalun(黄发伦)(SichuanUniversity)Abstract:Inthispaper,weinvestigatethebasicprope...  相似文献   

11.
题库建设中试题难度的修订和校准   总被引:1,自引:0,他引:1  
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.  相似文献   

12.
In order to evaluate the effectiveness of curricular or instructional innovations, researchers often attempt to measure change in students' conceptual understanding of the target subject matter. The measurement of change is therefore a critical endeavor. Often, this is accomplished through pre–post testing using an assessment such as a concept inventory, and aggregate test scores are compared from pre to post‐test in order to characterize gains. These comparisons of raw or normalized scores are most often made under the assumptions of Classical Test Theory (CTT). This study argues that measuring change at the item level (rather than the person level) on the Force and Motion Conceptual Evaluation (FMCE) can provide a more detailed insight into the observed change in students' Newtonian thinking. Further, such an approach is more warranted under the assumptions of Item Response Theory (IRT). In comparing item‐level measures of change under CTT and IRT measurement models, it was found that the inferences drawn from each analysis are similar, but those derived from IRT modeling stand on a stronger foundation statistically. Second, the IRT approach leads to analyzing common item groupings which provide further information about change at the item and topic level.  相似文献   

13.
考试质量的评价对教学管理决策至关重要.随着大规模标准化考试的不断涌现,对公正考试和科学评判的要求越来越高,阐述了IRT理论的原理及估算方法,并通过实证研究将IRT与经典测试理论(CTT)进行了理论比较,并基于中科院研究生院英语标准化考试的数据,从试题评价参数估计和考生能力估计等方面进行了实证对比.结果表明:IRT对项目参数的估计不依赖样本变化而变化,比CTT具有明显的稳定性;同时,IRT记分充分考虑了各个项目的性能差异,被试的得分更少雷同,更为精确.  相似文献   

14.
建立了关于Blaschke与调和Blaschke线性组合的射影体极的几个精度不同的Brunn-Minkowski型不等式,给出了调和Blaschke线性组合的质心体极的Brunn- Minkowski不等式和类似结果.  相似文献   

15.
The combination technique has repeatedly been shown to be an effective tool for the approximation with sparse grid spaces. Little is known about the reasons of this effectiveness and in some cases the combination technique can even break down. It is known, however, that the combination technique produces an exact result in the case of a projection into a sparse grid space if the involved partial projections commute.

The performance of the combination technique is analysed using a projection framework and the C/S decomposition. Error bounds are given in terms of angles between the spanning subspaces or the projections onto these subspaces. Based on this analysis modified combination coefficients are derived which are optimal in a certain sense and which can substantially extend the applicability and performance of the combination technique.  相似文献   


16.
将最大一最小贴近度与IOWA算子相结合,建立了基于最大一最小贴近度的IOWA算子最优组合预测模型,并且定义了在最大一最小贴近度下非劣性组合预测、预测方法优超等概念.在此模型下,研究了模型的非劣性组合预测及优性组合预测存在的充分条件.最后给出实例分析,表明该组合预测方法的有效性.  相似文献   

17.
We define the operations of an inessential combination and an almost inessential combination of models and theories. We establish basedness for an (almost) inessential combination of theories. We also establish that the properties of smallness and -stability are preserved upon passing to (almost) inessential combinations of theories. We define the notions of coloring of a model, colored model, and colored theory, and transfer the assertions about combinations to the case of colorings. We characterize the inessential colorings of a polygonometry.  相似文献   

18.
基于净现值的离散型多项目多期投资优化模型   总被引:1,自引:0,他引:1  
关于资本结构优化模型的讨论已经有了很好的结论,即基于项目组合的净现值最大化,对于多项目单期优化模型已经有了比较满意的结论.在已有结论的基础上研究了离散型多项目多期投资组合优化模型的一般形式,首先针对离散型多项目分期持续期相等的投资组合提出了一般优化模型,然后讨论离散型多项目分期持续期不全相等的投资组合优化模型,最后讨论了引进组合风险的投资组合优化模型。  相似文献   

19.
私募基金历来是高风险与高收益相伴而行的,根据Markowitz的思想,科学合理的构建私募基金投资组合方案,精确地刘划和分析私募基金投资组合模型及寻求优化,对求得私募基金管理、私募基金投资利益的保障和私募基金比较全有效的较高收益具有十分重要的意义。  相似文献   

20.
We consider a convex combination of matrices that arise in the study of communication networks and the corresponding convex combination of Kronecker squares of these matrices. We show that the spectrum of the first convex combination is contained in the spectrum of the second set and that the second largest eigenvalues coincide.  相似文献   

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