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1.
赵蕾  程国胜 《大学数学》2008,24(2):100-103
数据分析在计算机数据处理中占有重要地位.概念格理论是数据分析有力工具,本文以概念格为工具,讨论数据扩展而引起的相容性问题.主要是将数据作为概念格中的对象,在给定数据基本集并假设数据特征一定的条件下,考虑数据扩展相容性问题,解决了数据扩展的相容性判定问题并给出了相应的判定定理.目的是使在特征一定的情况下,数据对象达到最大化.  相似文献   

2.
数据驱动的决策支持系统概念及内涵   总被引:1,自引:0,他引:1  
从数据的观点出发,讨论了数据驱动的决策支持系统的概念及其内涵,对数据仓库、联机分析处理和数据挖掘等手段也进行了一定程度的讨论。另外,还对DSS数据和日常操作数据进行了分析,并给出了数据驱动的决策支持系统的基本结构。  相似文献   

3.
采用灰色系统预测理论对产品可靠性寿命试验数据进行预测,提出了建立产品可靠性寿命试验数据的灰色预测NGM(1,1)模型的方法,并通过采用试验数据序列与预测数据序列总体分布函数相等性检验方法确认灰色预测NGM(1,1)模型用于产品可靠性寿命试验数据预测是可行的.算例结果表明,采用灰色预测方法预测产品可靠性寿命试验数据并进行相关的分布函数参数估计有较高的精度,可达到缩短试验时间和节约试验费用目的.  相似文献   

4.
依据CPI经济序列数据确定性混沌原理,探讨自适应神经模糊推理系统模型构造,并给出此类混沌数据列预测的ANFIS系统结构形式,进行CPI经济序列数据预测.并用实例拟合、预测数据证明:ANFIS模型是一种精度较高的混沌数据序列预报系统.为CPI数据预测提供了一种计算方法.  相似文献   

5.
为2019年"高教社杯"全国大学生数学建模竞赛D题"空气质量数据的校准"给出了可行的解法,根据赛题所给的数据,对自建点数据和国控点数据进行了探索性数据分析,分析了自建点数据和国控点数据存在差异的原因,并采用多元线性回归模型和前馈神经网络模型对自建点数据进行统计学习和校准,并对学生在参赛中出现的方法进行了简要的说明与点评.  相似文献   

6.
李发勇 《数学通讯》2021,(3):27-28,F0004
在分析一道中考试题的图形和数据时,发现其中出现了数据不相容的错误,通过探究得到了关键数据的相容关系,并给出了该题的几种修正方案.  相似文献   

7.
在数据收集过程中,由于各种原因可能造成数据不完整的情况,并将严重影响数据挖掘的质量和结果的稳健性.本文基于EM算法,在SPSS软件的环境下,有效解决了一元线性模型下删失数据带来的参数估计问题,并将此方法实证推广到多元线性回归的模型中.  相似文献   

8.
高维大数据的相似性计算是数据挖掘领域的研究重点,论文通过分析高维大数据相似性计算的难点,提出采用可拓学的方法解决其中矛盾问题的研究思路。在基元表示高维大数据的基础上,借助数据转换、数据筛选、权重的确定、数据预处理等技术实现了数据之间的相似性计算,并基于水污染常规分析数据进行了算法验证。论文借助可拓的思想研究大数据相似性的问题,不仅对数据挖掘的研究有一定的理论促进,同时也为可拓学的研究提供了新的应用空间。  相似文献   

9.
粗糙集理论作为一种智能数据分析和数据挖掘的新的数学工具,其主要优点在于它不需要任何关于被处理数据的先验或额外知识.提出了一种基于粗糙集理论的智能数据分析模型,从目标数据集出发,通过数据预处理、数据分类和规则获取,实现对原始数据集的智能分析,并通过实例测试验证了该模型的有效性.  相似文献   

10.
数据群点的主轴表示该数据群点分布变异最大的若干方向,它是反映数据群点分布构造的主要特征之一。本论文提出一种对高维空间里数据群点主轴旋转运动的预测建模方法,并将其用于中国城市经济发展预测分析,可用于推测城市群体经济发展的主要特征方向  相似文献   

11.
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   

12.
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   

13.
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   

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.
采用三江平原湿地调查问卷结果作为原始数据,探讨了灰建模方法在条件价值法数据处理中的应用.在对问卷数据进行聚类分析的基础上,采用传统的GM(1,1)模型,得到了合理有效的灰色模型,改进了条件价值法数据建模中仅将支付与抗议支付作为两个基本变量的模型,得出了多分类模型.  相似文献   

16.
Material flow analysis is used to quantify the material turnover of a defined system, relying on data about flows and stocks from different sources with varying quality. In this study, the belief that the available data are representative for the value of interest is expressed via fuzzy sets, specifying the possible range of values of the data. A possibilistic framework for data reconciliation in MFA was developed and applied to a case study on wood flows in Austria. The framework consists of a data characterisation and a reconciliation step. Membership functions are defined based on the collected data and data quality assessment. Possible ranges and consistency levels (quantifying the agreement between input data and balance constraints) are determined. The framework allows problematic data and model weaknesses to be identified and can be used to illustrate the trade-off between confidence in the data and the consistency levels of resulting material flows.  相似文献   

17.
云计算和大数据已成为IT领域的研究热点,如何将云计算在数据存储和数据处理方面的优势应用于大数据领域具有重要的实际应用价值.开源的云平台OpenStack可方便地从硬件管理方面构建私有云,其存储模块Swift能够支持PB级的大数据存储.开源的云平台Hadoop在数据处理方面具有很强的优势,但在支持超大数据存储方面存在不足.通过对OpenStack中的存储模块Swift和Hadoop中的文件处理模块HDFS的比较分析,提出了将Swift和Hadoop的MapReduce技术结合来构建企业处理大数据的私有云计算系统方案.分析结果显示该方案是可行的,这种异构的私有云系统可以整合不同云计算平台各自的优势进行高效的大数据处理.  相似文献   

18.
Data reduction is an important issue in the field of data mining. The goal of data reduction techniques is to extract a subset of data from a massive dataset while maintaining the properties and characteristics of the original data in the reduced set. This allows an otherwise difficult or impossible data mining task to be carried out efficiently and effectively. This paper describes a new method for selecting a subset of data that closely represents the original data in terms of its joint and univariate distributions. A pair of distance criteria, motivated by the χ2-statistic, are used for measuring the goodness-of-fit between the distributions of the reduced and full datasets. Under these criteria, the data reduction problem can be formulated as a bi-objective quadratic program. A genetic algorithm technique is used in the search/optimization process. Experiments conducted on several real-world data sets demonstrate the effectiveness of the proposed method.  相似文献   

19.
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   

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