基于多元统计分析的城市竞争力研究

应用多元统计分析方法对34个省会城市和计划单列市的竞争力进行了综合评估.首先设立城市竞争力评价指标,由于指标之间存在相关性,采用因子分析法选取公共因子作为评价的综合指标,然后构造评价函数,根据城市竞争力在各公因子上的得分及其综合排名,分析各城市的发展特色和竞争优劣点.基于因子分析法得到的公因子替代原始变量,分别采用系统聚类分析法和K均值聚类分析法给各城市划分类型,比较两种不同聚类法得出的结果,分析聚类结果可靠性.最后基于综合评估结果给出了提高城市竞争力的合理建议.     

对编制数学学业成就测验的几点建议

一般来说,人们主要从两个角度来评价一个学业成就测验的好坏:一是从心理测量学的角度,看试题或试卷的各项指标是否符合心理测量学的要求,如题目的难度、区分度是否合理,试卷的信度、效度是否高,等等;二是看测验内容本身,是否与<标准>[1]的要求相一致、是否能够有效地代表所测查内容的评价范围、每一道试题是否测查了它想要测查的能力,等等.     

课堂教学评估中权重的制定方法探讨

本文介绍了多元统计分析在教学评估体系指标权重制定中的应用。结合具体例子用wilcox onsigned rank检验法和spearman相关系数对各种结果作了比较,并根据实际意义选出其中较好的结果作为评估函数。     

基于改进模糊综合评判的分销商评价研究

随着制造业逐渐向买方市场转变,供应链分销管理成为企业发展的驱动力之一。分销商在该环节发挥着关键作用,选择和管理分销商的前提是对其进行科学的评价。在回顾分销商评价方法的基础上,提出了基于模糊综合评判的分销商评价模型。针对传统模糊综合评判在指标赋权方面的不足,采用组合赋权法加以改进,首先对多种指标权数计算结果进行事前检验,根据检验结果确定最佳组合方式,然后通过事后检验保证组合权数的合理性。指标权数确定后,再经过因素集与评判集的确定、单因素评判、综合评判等阶段对分销商进行评价。最后将改进方法与传统方法进行了比较分析,并以某大型家电企业为例,验证了该方法能更为合理地解决分销商评价问题。     

用多种统计分析方法检验评价学生成绩与考试制度

余力．用多种统计分析方法检验评价学生成绩与考试制度．本文综合运用多元ＨｏｔｅｌｉｎｇＴ２检验方法和一元ｔ检验方法,对某校两组学生的学习成绩进行对比分析、评价。实例分析表明,“取消补考,完善重修制度”这一考试制度的改革方案是合理的,行之有效的,同时也是切实可行的。本文也初步尝试了处理病态数据的方法     

上市公司财务绩效的改进集成评价研究——以26家运输公司为例

为解决以往上市公司集成评价模型中各方法评价结果不一致问题,本文构建了改进集成评价模型。该模型先采用层次分析法、灰色关联度法、因子分析法进行评价,并运用KENDALL-W协和系数法对各评价结果进行事前一致性检验;通过检验后,再分别运用算术平均组合评价模型、Borda组合评价模型和Copeland组合评价模型进行组合评价。为了衡量组合评价与各评价方法的评价结果是否吻合,应用Spearman等级相关系数进行组合评价方法的事后检验,并根据Spearman等级相关系数的大小,选出最优的组合评价方法。最后,对中国26家上市运输公司财务绩效进行了集成评价的实证研究,并以算术平均组合评价模型的标准得分为聚类指标,采用欧氏距离法对26家上市运输公司进行聚类。结果显示:铁路、水路、公路运输各存在一个典型绩优企业,分别是:铁龙物流、北京传媒、海峡股份,四类上市运输公司中铁路上市公司财务绩效最优。     

改进模糊层次分析法在初级任职教育院校教学工作评价中的应用

针对初级任职教育院校教学工作评价指标多,体系复杂,难以完全量化评估的特点,引入改进的模糊层次分析法,为指标建立权重,并用相容性指标进行矩阵一致性检验,构建了模糊评价模型,提出了初级任职教育院校教学工作评价的多目标决策问题解决方案。该方法简便可行,可靠性好,与其它评价方法相比更加客观准确。     

应用模糊综合评判法对基础课—高等数学的课堂教学效果评估尝试

课程教育质量评估问题,是国家教委非常重视的问题。也是高等院校广大教师共同关心的问题。国家教委负责同志对教育质量评估问题多次作了专门报告。阐述评估的意义及内容。可见估评不仅能较客观地反映一个院校的教育水平。而且有利于调动“教”与“学”两方面的积极性,促进我国工科院校教学质量的提高。但如何进行课程教育评估,对我们来说,还是一项崭新的工作。特别是课程评估的各项指标如何制定,怎样进行“是化”,更是一项新的工作。为了做好这项工作,在这里,我们向大家推荐南京工学院教务处长,数学力学系付教授陶永德同志撰写的《应用模糊综合评判法对基础课—高等数学课堂教学效果进行评估尝试》一文,供高等工科院校广大数学教师参考,希望通过介绍这篇文章能引起讨论,更希望广大读者能就如何合理制定各项评估指标,使评估工作不仅能测试出课堂教学水平,而且有利于调动教师的积极性,有利于教学质量的提高。     

水泥品质指标比对检验结果的评估及分析

本文采用稳健统计分析技术,对水泥品质指标比对检验质检机构的质检水平进行了能力验证,结合散点图和柱状图,综合评价了各实验室的检测能力。     

基于集对分析的输电工程造价综合评价研究

合理评估输电工程造价水平对于提高电网资产效率,推动经济发展具有重要意义.综合考虑影响输电工程造价的量、价因素,构建了输电工程造价技术经济指标体系;基于AHP-熵权法确定指标基本权重,并建立三维权重模型反映电压等级与地区差异性对指标权重的影响;然后建立基于集对分析理论的综合评价模型,评估输电工程方案的造价水平;最后选取8个110kV、220kV输电工程进行分析,结果表明模型评价结果直观,能充分体现电压等级、地区的差异.     

A mixed integer programming model for multiple stage adaptive testing

The last decade has seen paper-and-pencil (P&P) tests being replaced by computerized adaptive tests (CATs) within many testing programs. A CAT may yield several advantages relative to a conventional P&P test. A CAT can determine the questions or test items to administer, allowing each test form to be tailored to a test taker’s skill level. Subsequent items can be chosen to match the capability of the test taker. By adapting to a test taker’s ability, a CAT can acquire more information about a test taker while administering fewer items. A Multiple Stage Adaptive test (MST) provides a means to implement a CAT that allows review before the administration. The MST format is a hybrid between the conventional P&P and CAT formats. This paper presents mixed integer programming models for MST assembly problems. Computational results with commercial optimization software will be given and advantages of the models evaluated.     

基于集对分析的组合评价模型及其应用

组合评价是目前处理单一评价方法的不一致性、提高评价结果的可靠性和合理性的有效途径,现有的组合评价方法的主要不足是对这些单一评价法的评价排序值之间的一致性信息利用尚不够充分.提出用集对分析方法的联系度从同、异、反三方面定量描述这些一致性信息、并用于构造模糊互补判断矩阵来确定各单一评价法的组合权重的新模型(CEM-SPA).CEM-SPA的应用结果表明:CEM-SPA的组合评价结果比单一评价法更具有可靠性和合理性,与各单一评价法的相容性均很高;CEM-SPA利用各单一评价法的相容性测度确定各单一评价法的权重,利用各单一评价法的信息比常用的平均值法更充分因而显得更为合理;CEM-SPA在基于评价排序值的系统组合评价中具有推广应用价值.     

New lower bounds for the three-dimensional finite bin packing problem

The three-dimensional finite bin packing problem (3BP) consists of determining the minimum number of large identical three-dimensional rectangular boxes, bins, that are required for allocating without overlapping a given set of three-dimensional rectangular items. The items are allocated into a bin with their edges always parallel or orthogonal to the bin edges. The problem is strongly NP-hard and finds many practical applications. We propose new lower bounds for the problem where the items have a fixed orientation and then we extend these bounds to the more general problem where for each item the subset of rotations by 90° allowed is specified. The proposed lower bounds have been evaluated on different test problems derived from the literature. Computational results show the effectiveness of the new lower bounds.     

Qualitative factors in data envelopment analysis: A fuzzy number approach

Qualitative factors are difficult to mathematically manipulate when calculating the efficiency in data envelopment analysis (DEA). The existing methods of representing the qualitative data by ordinal variables and assigning values to obtain efficiency measures only superficially reflect the precedence relationship of the ordinal data. This paper treats the qualitative data as fuzzy numbers, and uses the DEA multipliers associated with the decision making units (DMUs) being evaluated to construct the membership functions. Based on Zadeh’s extension principle, a pair of two-level mathematical programs is formulated to calculate the α-cuts of the fuzzy efficiencies. Fuzzy efficiencies contain more information for making better decisions. A performance evaluation of the chemistry departments of 52 UK universities is used for illustration. Since the membership functions are constructed from the opinion of the DMUs being evaluated, the results are more representative and persuasive.     

A queueing model for general group screening policies and dynamic item arrivals

Classification of items as good or bad can often be achieved more economically by examining the items in groups rather than individually. If the result of a group test is good, all items within it can be classified as good, whereas one or more items are bad in the opposite case. Whether it is necessary to identify the bad items or not, and if so, how, is described by the screening policy. In the course of time, a spectrum of group screening models has been studied, each including some policy. However, the majority ignores that items may arrive at random time epochs at the testing center in real life situations. This dynamic aspect leads to two decision variables: the minimum and maximum group size. In this paper, we analyze a discrete-time batch-service queueing model with a general dependency between the service time of a batch and the number of items within it. We deduce several important quantities, by which the decision variables can be optimized. In addition, we highlight that every possible screening policy can, in principle, be studied, by defining the dependency between the service time of a batch and the number of items within it appropriately.     

模式识别的Fuzzy统计方法及应用

运用模糊数学的概念和方法对具有模糊性的观测结果进行处理和识别 ,构成了模糊模式识别的基本内容 .利用 Fuzzy统计的方法建立了模式识别的数学模型 ,并编出模型的计算机程序 .按照科技部、教育部关于科研评价的“目标导向、分类实施、客观公正、注重实效”的要求 ,将上述程序应用于科研项目的评审中 ,克服了以往评审过程单一化、主观化的缺点 ,使评审客观、公正、合理 ,易于操作 .     

改进差分进化算法求解装载率凹费用装箱问题

研究了广泛存在于物流作业中一类新型的装箱问题,主要特征体现在箱子使用费用是关于装载率的凹函数。为求解问题,提出了一种基于分组编码策略的改进差分进化算法,以避免常规实数和整数编码方法存在放大搜索空间的不足。针对分组编码策略,定制化设计了以促进优秀基因传播为导向的新型变异和交叉操作,另外还嵌入了以物品置换为邻域的自适应局部搜索操作以增强局部搜索能力。对以往文献给出算例在不同凹费用函数下进行测试,实验结果显示所提出的算法明显优于BFD启发式算法,并且较遗传算法也有显著性改进。     

Item efficiency: an item response theory parameter with applications for improving the reliability of mathematics assessment

Many large universities, community colleges and some smaller four-year colleges are turning to hybrid or online instruction for remedial and entry level mathematics courses, often assessed using online exams in a proctored computer lab environment. Faculty face the task of choosing questions from a publisher's text bank with very little, if any, background in test theory and design. We present a new item parameter, item efficiency, that is calculated from the results of an item response theory analysis of a comprehensive college algebra final examination and show that this new parameter may be used to identify items better suited for similar comprehensive final assessments. Further, by relating Item Efficiency to classical test theory item statistics, we propose guidelines that can be used to identify suitable items prior to testing with little or no background in psychometric theory.     

Space defragmentation for packing problems

One of main difficulties of multi-dimensional packing problems is the fragmentation of free space into several unusable small parts after a few items are packed. This study proposes a defragmentation technique to combine the fragmented space into a continuous usable space, which potentially allows the packing of additional items. We illustrate the effectiveness of this technique using the two- and three-dimensional bin packing problem, where the aim is to load all given items (represented by rectangular boxes) into the minimum number of identical bins. Experimental results based on well-known 2D and 3D bin packing data sets show that our defragmentation technique alone is able to produce solutions approaching the quality of considerably more complex meta-heuristic approaches for the problem. In conjunction with a bin shuffling strategy for incremental improvement, our resultant algorithm outperforms all leading meta-heuristic approaches based on the commonly used benchmark data by a significant margin.     

Factors associated with middle-school mathematics achievement in Greece: the case of algebra

This study presents a subset of factors and their association with students’ achievement in school algebra. The participants were students who had enrolled in 2007 at the ninth year of Greek public education (third year of middle school). A total of 735 students participated (aged 14–15 years) from 37 public secondary schools. The sample consisted of 378 girls (51.4%) and 357 boys (48.6%). A written algebra test and a questionnaire including demographic survey items were used to collect data. The results show that attitude towards mathematics (ATM) and the current teacher rating of mathematics performance were identified as the more significant predictors of algebra achievement, contributing by 18.1% and 24.7%, respectively, in total variance of mean at the end of ninth grade.