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1.
多元相关的聚类分析法在企业效绩评价中的运用   总被引:2,自引:0,他引:2  
运用多元函数相关分析中的聚类分析法 ,根据由指标数据形成的矩阵 ,计算确定各项指标的权数 ,建立效绩评价的测定方程 ,对各企业效绩进行测定和评价 .  相似文献   

2.
以47例重症病毒性肝炎病人为研究对象,以肝功能的7个指标的初始测定值为数据来源,对单项指标和多项指标组合分别应用模糊模式识别的直接方法,通过结果的比较,找到了兼顾正确率、敏感性和特异性的最佳指标组合,最后探讨了本文方法的优点和不足之处.  相似文献   

3.
分析上海世博会在世博筹备建设和举办时期对上海市经济方面影响.筛选了世博会影响经济的四个方面(国民经济,财政收支,固定资产投资和对外经济贸易与旅游)的10个主要指标,构建了世博会影响经济的评价指标体系,针对每一项指标,利用1995年到2002的实际数据用指数回归拟合模型测算出2003-2010年在未筹办世博会情况下各项经济指标的估计(拟合)数据,并建立单指标的影响力指数模型,在分析2003年后的实际数据与拟合数据差异基础上,获得了上海世博会在每个指标方面对上海的影响力指数;建立了多指标综合影响力指数模型,得出总的经济影响力的指数为0.2403.考虑到2008年底金融危机势必会削弱世博会对经济的影响,通过参照另外两个同为中国直辖市的重庆和天津相同指标的变化,运用单独建立的模型,剔除金融危机对经济的影响,从而获得更客观地揭示世博对上海地区经济的真实影响程度.并就两个典型的指标给出了具体的演算过程,最后得到了消除了金融危机后的所有指标的影响力指数值,最终获得总的经济影响力的指数为0.2531,即世博会对上海市经济的实际贡献率为25.31%.  相似文献   

4.
为实现对煤炭种类的快速有效煤质识别,选取实验室实测的十六种煤样的十项煤质特性指标数据,分别利用多功能多元素综合分析仪进行碳、氢、氧、硫元素测定,利用透反射偏光显微镜进行镜质组、丝质组和壳质组三大显微组分测定,利用电子天平称量法进行了块状颗粒体比例和粒状颗粒体比例测定.对近邻函数准则识别算法进行改进,采用隶属关系矩阵替代基于近邻函数准则识别算法中的距离矩阵,并利用欧氏距离法构造隶属关系矩阵,增强了煤质特性指标数据间的关联性.通过煤质识别实例分析,计算改进的煤质特性指标近邻函数矩阵与类内类间连接损失量,得到烟煤的总损失最小,进而判定煤样16属于烟煤一类.结果与实际相符,证明了方法的实用性和正确性,对煤质检测部门和煤炭勘探部门具有一定借鉴意义.  相似文献   

5.
参照国内外现有的可持续发展指标体系,基于"两型社会"建设的视角,根据长株潭地区的具体特征以及数据的可得性,建立了包含经济社会与资源环境2个一级指标21个二级指标的长株潭可持续发展指标体系,并采用2000到2011年年度数据对长株潭地区可持续发展进行了评估与分析.研究结果显示,长株潭地区的生态环保指标综合得分已从2004年前的小于经济社会指标综合得分变为当前的大于经济社会指标综合得分;地区可持续发展度已从2000年前的非可持续逐渐过渡到现在的接近高可持续性,意味着"两型社会"第一阶段的各项目标任务已基本完成.但产业转型难将会成为长株潭整体辐射区生态环境优化的重要瓶颈.  相似文献   

6.
教学质量评估的统计分析法   总被引:7,自引:0,他引:7  
教学评估是一项主观性很强的工作 ,因而是复杂的 ,其结果很可能偏离被评估对象的根本属性。为确保评估的公正、科学、准确 ,有必要对实测数据进行统计分析。本文首先采用稳定度检验和卡方检验来分析各项指标的评估结果是否具有可信性 ;其次 ,通过对各项指标评价结果的集中趋势进行统计分析 ,以检验量化误差是否在可接受的范围内 ;最后 ,运用符号秩次检验法对各项评估指标的权重是否合理进行统计分析。这些统计分析方法的应用 ,经实践证明是合理的 ,能够衡量评价结果的真实程度 ,从而保证了教学质量评估工作的顺利进行  相似文献   

7.
在分析各项影响因素分级标准的基础上,建立了三维土工网护坡侵蚀稳定性的综合评价体系.针对三维土工网边坡侵蚀稳定性分析中不确定性问题,将云模型理论引入到综合评判中,实现了定性与定量的不确定性转换.通过构建前件云发生器和后件云发生器,利用不确定推理,确定各项评价指标的具体分值.借助层次分析法与敏感度分析确定各项评价指标的权重,进而得出综合评价体系的整体得分.工程实例计算结果证实了模型的实用性和有效性,为三维土工网防护边坡侵蚀稳定性的评价提供了一条新的途径.  相似文献   

8.
从人员招聘中属性的不完全补偿性出发,借助定性定量相结合的方法获取了评估数据,并对定性指标进行了差异性分析,增强主观评价指标的准确性.通过指标之间归一化处理,获取具有公度性的数据,并以图书馆人员的招聘为例,构架了一般的人员招聘评价模型,获得了较为理想的结果.  相似文献   

9.
郭荣 《珠算》2008,(10):20-21
如果说企业是一辆客车,财务报表中的各项指标就是仪表盘里显示的数据,我们只有依靠这些数据,才能掌握客车的整体情况,并保证它安全前行。  相似文献   

10.
为实现页岩气水平井压裂层段精细开发,总结并筛选出了合适的段评价指标,利用测完井数据计算了水平井段各项指标参数,基于提出的段指标评价体系,采用层次分析法和熵值法相结合的组合权重方法开展了指标权重计算,通过乘法合成形式将标准化指标值和组合权重进行结合并建立水平井段评价模型,以重庆市涪陵区焦石坝A1井为例进行验证与应用,评价结果表明:A1井水平段整体处于中等甜点区,物性和可压裂性较好;与FSI产气剖面对比,段评价指数和与单段产气量具有较好的正相关关系,本评价模型能有效避免A1井第4段和第6段的无效性,以期为水平井精细开发时提供参考.  相似文献   

11.
Because similarities in biological sequences often suggest similarities in structures and functions, profile searches using multiple alignment of families of related biological sequences provide useful hints for starting points for experimental investigations in molecular biology. Strategies are formulated for determining statistical significance of scores obtained by searching multiple alignment profiles with databanks, while accommodating for gaps in the profile. The methodology is validated with derivation of asymptotic distribution of the maximum of profile scores, even under weakly dependence conditions. Simulation studies show the proposed method is adequate for moderate sample sizes. The methodology is illustrated with an immunoglobulin protein domain study example.  相似文献   

12.
A daunting challenge in the area of computational biology has been to develop a method to theoretically predict the correct three-dimensional structure of a protein given its linear amino acid sequence. The ability to surmount this challenge, which is known as the protein folding problem, has tremendous implications. We introduce a novel ab initio approach for the protein folding problem. The accurate prediction of the three-dimensional structure of a protein relies on both the mathematical model used to mimic the protein system and the technique used to identify the correct structure. The models employed are based solely on first principles, as opposed to the myriad of techniques relying on information from statistical databases. The framework integrates our recently proposed methods for the prediction of secondary structural features including helices and strands, as well as -sheet and disulfide bridge formation. The final stage of the approach, which culminates in the tertiary structure prediction of a protein, utilizes search techniques grounded on the foundations of deterministic global optimization, powerful methods which can potentially guarantee the correct identification of a protein's structure. The performance of the approach is illustrated with bovine pancreatic trypsin inhibitor protein and the immunoglobulin binding domain of protein G.  相似文献   

13.
With the broad development of the World Wide Web, various kinds of heterogeneous data (including multimedia data) are now available to decision support tasks. A data warehousing approach is often adopted to prepare data for relevant analysis. Data integration and dimensional modeling indeed allow the creation of appropriate analysis contexts. However, the existing data warehousing tools are well-suited to classical, numerical data. They cannot handle complex data. In our approach, we adapt the three main phases of the data warehousing process to complex data. In this paper, we particularly focus on two main steps in complex data warehousing. The first step is data integration. We define a generic UML model that helps representing a wide range of complex data, including their possible semantic properties. Complex data are then stored in XML documents generated by a piece of software we designed. The second important phase we address is the preparation of data for dimensional modeling. We propose an approach that exploits data mining techniques to assist users in building relevant dimensional models.  相似文献   

14.
Temporal data are information measured in the context of time. This contextual structure provides components that need to be explored to understand the data and that can form the basis of interactions applied to the plots. In multivariate time series, we expect to see temporal dependence, long term and seasonal trends, and cross-correlations. In longitudinal data, we also expect within and between subject dependence. Time series and longitudinal data, although analyzed differently, are often plotted using similar displays. We provide a taxonomy of interactions on plots that can enable exploring temporal components of these data types, and describe how to build these interactions using data transformations. Because temporal data are often accompanied other types of data we also describe how to link the temporal plots with other displays of data. The ideas are conceptualized into a data pipeline for temporal data and implemented into the R package cranvas. This package provides many different types of interactive graphics that can be used together to explore data or diagnose a model fit.  相似文献   

15.
Abstract

Statistical software systems include modules for manipulating data sets, model fitting, and graphics. Because plots display data, and models are fit to data, both the model-fitting and graphics modules depend on the data. Today's statistical environments allow the analyst to choose or even build a suitable data structure for storing the data and to implement new kinds of plots. The multiplicity problem caused by many plot varieties and many data representations is avoided by constructing a plot-data interface. The interface is a convention by which plots communicate with data sets, allowing plots to be independent of the actual data representation. This article describes the components of such a plot-data interface. The same strategy may be used to deal with the dependence of model-fitting procedures on data.  相似文献   

16.
We consider the implications of streaming data for data analysis and data mining. Streaming data are becoming widely available from a variety of sources. In our case we consider the implications arising from Internet traffic data. By implication, streaming data are unlikely to be time homogeneous so that standard statistical and data mining procedures do not necessarily apply. Because it is essentially impossible to store streaming data, we consider recursive algorithms, algorithms which are adaptive and discount the past and also algorithms that create finite pseudo-samples. We also suggest some evolutionary graphics procedures that are suitable for streaming data. We begin our discussion with a discussion of Internet traffic in order to give the reader some sense of the time and data scale and visual resolution needed for such problems.  相似文献   

17.
SVM解决两分类问题时,在大规模数据上训练速度很慢,利用数据提取的方法可以减少训练样本数目,加快训练速度。本文利用马氏距离和"aσ-方法"提出新的数据提取方法,根据样本点到训练集的马氏距离来确定样本点与样本集的位置关系,只提取对于建立超平面有作用的样本点,避免了以往数据提取方法的随机性;并考虑提取的数据占原来总样本集数目的比例,通过调整a的值,控制数据提取的数量,避免提取后训练样本集的数据太多或太少,从而加快SVM的训练速度。  相似文献   

18.
高质量的决策越来越依赖于高质量的数据挖掘及其分析,高质量的数据挖掘离不开高质量的数据.在大型仪器利用情况调查中,由于主客观因素,总是致使有些数据出现异常,影响数据的质量.这就需要通过适用的方法对异常数据进行检测处理.不同类型数据往往需要不同的异常值检测方法.分析了大型仪器利用情况调查数据的总体特点、一般方法,并以国家科技部平台中心主持的"我国大型仪器资源现状调查"(2009)中大型仪器使用机时和共享机时数据为主线,比较研究了回归方法、基于深度的方法和箱线图方法等对不同类型数据异常值检测的适用性.选取不同角度,检验并采用不同的适用方法,找出相关的可疑异常值,有助于下一步有效开展大型仪器利用情况异常数据的分析处理,提高数据质量,为大型仪器利用情况综合评价奠定基础,也为科技资源调查数据预处理中异常值检测方法提供有益借鉴.  相似文献   

19.
宗威  吴锋  刘玮 《运筹与管理》2019,28(10):175-183
大数据时代下,外界数据源的快速变化为保证企业信息系统中动态数据的及时性带来巨大挑战。以企业资源计划(Enterprise Resource Planning, ERP)系统中动态的采购数据为研究对象,从数据应用角度研究如何以及何时更新ERP系统中的采购数据,从而使系统更新成本与数据过时成本最优的问题。将ERP系统中采购数据动态更新过程刻画为马尔科夫决策过程,设计了求解数据最优更新策略的动态规划算法。通过数值分析的对比结果发现,相对于传统的基于固定周期的数据更新策略而言,应用驱动的非固定周期动态数据更新策略不仅能有效保证动态数据的及时性,还能够有效降低企业的数据更新成本。  相似文献   

20.
A continuous extension of the objective function to a projective space guarantees that for each data set there exists at least one hyperplane or hypersphere minimizing the average squared distance to the data. For data sufficiently close to a hypersphere, as the collinearity of the data increases, so does the sensitivity of the fitted hypersphere to perturbations of the data.

  相似文献   


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