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1.
分类是文本信息搜索和挖掘的核心内容,被广泛应用于搜索引擎的设计以及数据挖掘的研究中。首先对文本进行分词,对分词的结果采用x2统计量的方法提取特征,再使用前向神经网络的交叉覆盖算法作为分类器进行文本分类。实验表明,x2统计量可大规模降低特征维数,在此基础上结合交叉覆盖算法的优秀分类能力,可在特征维数较低的情况下获得一个性能较好的文本分类器。  相似文献   

2.
文本分类是信息检索和数据挖掘的基础,被广泛应用于网络数据挖掘及搜索引擎等方面。首先对文本进行分词,对分词的结果分别使用x2统计量(CHI)方法与相关系数法(CC法)进行降维,并使用维数调节的思想进行特征提取。在得到特征集后,使用覆盖算法作为文本分类器进行学习。实验结果表明,通过结合相关系数法、覆盖算法以及维数调节方法,可实现一个效果较好的文本分类器。  相似文献   

3.
覆盖算法下文本分类特征选择的研究   总被引:1,自引:1,他引:0  
文本分类是信息检索和数据挖掘的基础,被广泛应用于网络数据挖掘及搜索引擎等方面.首先对文本进行分词,对分词的结果分别使用x2统计量(CHI)方法与相关系数法(CC法)进行降维,并使用维数调节的思想进行特征提取.在得到特征集后,使用覆盖算法作为文本分类器进行学习.实验结果表明,通过结合相关系数法、覆盖算法以及维数调节方法,可实现一个效果较好的文本分类器.  相似文献   

4.
文本分类是信息检索和数据挖掘中的重要主题之一.文中提出了一种基于贪婪覆盖算法的文本分类方法,首先对文本进行分词,分词的结果用CHI统计量的方法提取特征,使用TF-IDF-ICSD进行特征权重计算.对贪婪覆盖算法采用另一种选取初始点的方法来构建分类器,用复旦大学语料库作为测试数据集,并与BP算法相比较.实验结果表明文本提出的方法是有效的.  相似文献   

5.
利用CHI值特征选取和前向神经网络的覆盖算法,通过对文本进行分词的预处理后,实现文本的自动分类。该方法利用CHI值进行特征选取即特征降维,应用覆盖算法进行文本分类。该方法将CHI值特征选取和覆盖算法充分结合,在提高了分类速度的同时还保证了分类的准确度。应用该方法对标准数据集中的文本进行实验,并在不同的维数上与SVM算法、朴素贝叶斯方法的实验结果进行了比较。结果表明,与SVM算法和朴素贝叶斯方法相比较,覆盖算法在准确度上更好。并且,维数的选择对分类的精确度影响很大。  相似文献   

6.
基于CHI值特征选取和覆盖的文本分类方法   总被引:1,自引:1,他引:0  
利用CHI值特征选取和前向神经网络的覆盖算法,通过对文本进行分词的预处理后,实现文本的自动分类.该方法利用CHI值进行特征选取即特征降维,应用覆盖算法进行文本分类.该方法将CHI值特征选取和覆盖算法充分结合,在提高了分类速度的同时还保证了分类的准确度.应用该方法对标准数据集中的文本进行实验,并在不同的维数上与SVM算法、朴素贝叶斯方法的实验结果进行了比较.结果表明,与SVM算法和朴素贝叶斯方法相比较,覆盖算法在准确度上更好.并且,维数的选择对分类的精确度影响很大.  相似文献   

7.
提出了一种实体关系抽取方案,该方案针对实体关系抽取中特征空间维数过高问题,引入了文本分类中的特征选择算法,如信息增益、期望交叉熵和x2统计,实现了特征空间降维。实验结果表明,各特征选择算法均能在尽量保证抽取性能的同时有效地降低向量空间维数,提高分类效率,其中x2统计取得的效果最好。  相似文献   

8.
白云晖 《福建电脑》2008,24(7):113-114
本文利用信息增益特征选取和前向神经网络的覆盖算法,对文本进行分词的预处理后,实现文本的自动分类。该方法将信息增益特征选取和覆盖算法充分结合,不但提高了分类速度,还保证了分类的准确度。应用该方法对标准数据集中的文本进行实验,并在不同的维数上与SVM算法,贝叶斯方法的实验结果进行了比较。  相似文献   

9.
基于交叉覆盖算法的中文文本分类   总被引:1,自引:0,他引:1       下载免费PDF全文
基于向量空间模型的文本分类过程中遇到的最大问题就是以词为特征项的向量维数太大,需要进行特征选取,而交叉覆盖算法的输入集是n维欧式空间的点集,可以忽略维数的大小,从而最大程度上精确地表示文本,然后再进行分类,能够大大提高正确率。将交叉覆盖算法作为一种分类算法来进行中文文本分类,取得了不错的效果,在封闭测试中的准确率达到98.32%。  相似文献   

10.
特征选择在文本挖掘技术中是一个关键部分.训练集中的文本逐个经过分词后,可形成文本分类系统的全特征空间,一般情况下,这个空间的维数都会较大,可达到几十万维.经过特征选择之后,在降低噪声的同时,特征空间的维数得以压缩,最终能提高分类算法的速度和分类精度.本文从传统的Ml(Mutual Infomation)出发,并对它进行...  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

18.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

19.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

20.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

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