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1.
基于最小二乘支持向量机变形,得到一个极其简单快速的分类器--直接支持向量机.与最小二乘支持向量机相比,该分类器只需直接求解一个更小规模矩阵的逆,大大减小了计算量,并未降低分类精度.从理论上证明了该矩阵可逆,保证了分类面存在的唯一性.对于线性情形,采用Sherman-Morrison-Woodbury公式降低可逆矩阵的维数,进一步减少了计算复杂度,使其可适用于更大规模的样本集.数值实验表明,新分类器可行并具有上述优势.  相似文献   

2.
以医疗数据为应用对象,应用网格搜索和交叉验证的方法选择参数,建立最小二乘支持向量机分类器,进行实际验证,并与使用K近邻分类器(K-NN)和C4.5决策树两种方法的结果进行比较.结果表明,LS-SVM分类器取得较高的准确率,表明最小二乘支持向量机在医疗诊断研究中具有很大的应用潜力.  相似文献   

3.
最小二乘支持向量机采用最小二乘线性系统代替传统的支持向量即采用二次规划方法解决模式识别问题,能够有效地减少计算的复杂性。但最小二乘支持向量机失去了对支持向量的稀疏性。文中提出了一种基于边界近邻的最小二乘支持向量机,采用寻找边界近邻的方法对训练样本进行修剪,以减少了支持向量的数目。将边界近邻最小二乘支持向量机用来解决由1-a-r(one-against-rest)方法构造的支持向量机分类问题,有效地克服了用1-a-r(one-against-rest)方法构造的支持向量机分类器训练速度慢、计算资源需求比较大、存在拒分区域等缺点。实验结果表明,采用边界近邻最小二乘支持向量机分类器,识别精度和识别速度都得到了提高。  相似文献   

4.
最小二乘支持向量机采用最小二乘线性系统代替传统的支持向量即采用二次规划方法解决模式识别问题,能够有效地减少计算的复杂性.但最小二乘支持向量机失去了对支持向量的稀疏性.文中提出了一种基于边界近邻的最小二乘支持向量机,采用寻找边界近邻的方法对训练样本进行修剪,以减少了支持向量的数目.将边界近邻最小二乘支持向量机用来解决由1-a-r(one-against-rest)方法构造的支持向量机分类问题,有效地克服了用1-a-r(one-against-rest)方法构造的支持向量机分类器训练速度慢、计算资源需求比较大、存在拒分区域等缺点.实验结果表明,采用边界近邻最小二乘支持向量机分类器,识别精度和识别速度都得到了提高.  相似文献   

5.
基于支持向量机和最小二乘支持向量机的入侵检测比较   总被引:2,自引:0,他引:2  
将支持向量机和最小二乘支持向量机用于入侵检测之中,利用主元分析对数据进行约简,然后使用SVM和 LS-SVM对数据进行训练和测试.基于KDDCUP'99做了三组对比实验,对支持向量机和最小二乘支持向量机的性能做了统计.实验结果表明,SVM比LS-SVM分类能力强,但是LS-SVM耗时较少.  相似文献   

6.
一种高效的最小二乘支持向量机分类器剪枝算法   总被引:2,自引:0,他引:2  
针对最小二乘支持向量机丧失稀疏性的问题,提出了一种高效的剪枝算法.为了避免解初始的线性代数方程组,采用了一种自下而上的策略.在训练的过程中,根据一些特定的剪枝条件,块增量学习和逆学习交替进行,一个小的支持向量集能够自动形成.使用此集合,可以构造最终的分类器.为了测试新算法的有效性,把它应用于5个UCI数据集.实验结果表明:使用新的剪枝算法,当增量块的大小等于2时,在几乎不损失精度的情况下,可以得到稀疏解.另外,和SMO算法相比,新算法的速度更快.新的算法不仅适用于最小二乘支持向量机分类器,也可向最小二乘支持向量回归机推广.  相似文献   

7.
应用非线性最小二乘支持向量机对原核生物进行基因识别,通过寻找序列开放阅读框(ORF),并与可靠基因位点文件进行比较产生训练样本集,然后提取样本GC含量和Z曲线特征,并利用T检验方法检验各特征值所包含的信息量,设计出了非线性最小二乘支持向量机分类器识别基因.结果表明非线性最小二乘支持向量机的识别率比Fisher判别和线性支持向量机在不同的特征组合下分别提高了7.09%~29.97%和10.97%~25.45%,并且在特征值信息量较小的情况下非线性最小二乘支持向量机更能表现其优越性.  相似文献   

8.
一种新型的多元分类支持向量机   总被引:3,自引:0,他引:3  
最小二乘支持向量机采用最小二乘线性系统代替传统的支持向量机采用二次规划方法解决模式识别问题。该文详细推理和分析了二元分类最小二乘支持向量机算法,构建了多元分类最小二乘支持向量机,并通过典型样本进行测试,结果表明采用多元分类最小二乘支持向量机进行模式识别是有效、可行的。  相似文献   

9.
一种改进的最小二乘支持向量机及其应用   总被引:3,自引:0,他引:3       下载免费PDF全文
为了克服传统支持向量机训练速度慢、计算资源需求大等缺点,本文应用最小二乘支持向量机算法来解决分类问题。同时,本文指出了决策导向循环图算法的缺陷,采用自适应导向循环图思想来实现多类问题的分类。为了提高样本的学习速度,本文还将序贯最小优化算法与最小二乘支持向量机相结合,最终形成了ADAGLSSVM算法。考虑到最小二
乘支持向量机算法失去了支持向量的稀疏性,本文对支持向量作了修剪。实验结果表明,修剪后,分类器的识别精度和识别速度都得到了提高。  相似文献   

10.
将支持向量机应用于故障的分类诊断,通过实例建立了两类故障分类器和多故障分类器,给出了具体的建立多故障分类器的步骤和仿真结果。最后提出了一种新的方法——基于支持向量机的并行诊断网络。  相似文献   

11.
一种贝叶斯证据框架下支持向量机建模方法的研究   总被引:14,自引:1,他引:14       下载免费PDF全文
研究贝叶斯证据框架下标准支持向量机和最小二乘支持向量机的估计算法和建模方法,给出一种高斯桉支持向量机估计算法的参数选择和调整方法,将贝叶斯证据框架下支持向量机的建模方法应用于非线性系统的辨识,仿真结果表明,该方法对于工业过程建模是十分有效的。  相似文献   

12.
Support vector machines (SVMs) are one of the most popular methodologies for the design of pattern classification systems with sound theoretical foundations and high generalizing performance. The SVM framework focuses on linear and nonlinear models that maximize the separating margin between objects belonging in different classes. This paper extends the SVM modeling context toward the development of additive models that combine the simplicity and transparency/interpretability of linear classifiers with the generalizing performance of nonlinear models. Experimental results are also presented on the performance of the new methodology over existing SVM techniques.  相似文献   

13.
Support vector machine (SVM) is a supervised machine learning approach that was recognized as a statistical learning apotheosis for the small-sample database. SVM has shown its excellent learning and generalization ability and has been extensively employed in many areas. This paper presents a performance analysis of six types of SVMs for the diagnosis of the classical Wisconsin breast cancer problem from a statistical point of view. The classification performance of standard SVM (St-SVM) is analyzed and compared with those of the other modified classifiers such as proximal support vector machine (PSVM) classifiers, Lagrangian support vector machines (LSVM), finite Newton method for Lagrangian support vector machine (NSVM), Linear programming support vector machines (LPSVM), and smooth support vector machine (SSVM). The experimental results reveal that these SVM classifiers achieve very fast, simple, and efficient breast cancer diagnosis. The training results indicated that LSVM has the lowest accuracy of 95.6107 %, while St-SVM performed better than other methods for all performance indices (accuracy = 97.71 %) and is closely followed by LPSVM (accuracy = 97.3282). However, in the validation phase, the overall accuracies of LPSVM achieved 97.1429 %, which was superior to LSVM (95.4286 %), SSVM (96.5714 %), PSVM (96 %), NSVM (96.5714 %), and St-SVM (94.86 %). Value of ROC and MCC for LPSVM achieved 0.9938 and 0.9369, respectively, which outperformed other classifiers. The results strongly suggest that LPSVM can aid in the diagnosis of breast cancer.  相似文献   

14.
Fuzzy functions with support vector machines   总被引:1,自引:0,他引:1  
A new fuzzy system modeling (FSM) approach that identifies the fuzzy functions using support vector machines (SVM) is proposed. This new approach is structurally different from the fuzzy rule base approaches and fuzzy regression methods. It is a new alternate version of the earlier FSM with fuzzy functions approaches. SVM is applied to determine the support vectors for each fuzzy cluster obtained by fuzzy c-means (FCM) clustering algorithm. Original input variables, the membership values obtained from the FCM together with their transformations form a new augmented set of input variables. The performance of the proposed system modeling approach is compared to previous fuzzy functions approaches, standard SVM, LSE methods using an artificial sparse dataset and a real-life non-sparse dataset. The results indicate that the proposed fuzzy functions with support vector machines approach is a feasible and stable method for regression problems and results in higher performances than the classical statistical methods.  相似文献   

15.
提出了一种用支持向量机辨识系统状态空间模型的非线性离散动力学系统控制新方法. 在本方法中, 采用最小二乘支持向量机在每一个工作点辨识非线性系统的局部最优线性化模型. 针对该模型, 采用常规的线性控制方法在每个工作点设计局部线性控制器, 并在整个控制任务的每个工作点重复此设计过程.用该方法对两个典型的非线性离散系统采用极点配置技术进行了仿真验证, 结果显示系统对参考输入具有满意的跟踪性能, 证明该方法是有效和可行的.  相似文献   

16.
Type-2 fuzzy logic-based classifier fusion for support vector machines   总被引:1,自引:0,他引:1  
As a machine-learning tool, support vector machines (SVMs) have been gaining popularity due to their promising performance. However, the generalization abilities of SVMs often rely on whether the selected kernel functions are suitable for real classification data. To lessen the sensitivity of different kernels in SVMs classification and improve SVMs generalization ability, this paper proposes a fuzzy fusion model to combine multiple SVMs classifiers. To better handle uncertainties existing in real classification data and in the membership functions (MFs) in the traditional type-1 fuzzy logic system (FLS), we apply interval type-2 fuzzy sets to construct a type-2 SVMs fusion FLS. This type-2 fusion architecture takes considerations of the classification results from individual SVMs classifiers and generates the combined classification decision as the output. Besides the distances of data examples to SVMs hyperplanes, the type-2 fuzzy SVMs fusion system also considers the accuracy information of individual SVMs. Our experiments show that the type-2 based SVM fusion classifiers outperform individual SVM classifiers in most cases. The experiments also show that the type-2 fuzzy logic-based SVMs fusion model is better than the type-1 based SVM fusion model in general.  相似文献   

17.
This article introduces an approach to identify unknown nonlinear systems by fuzzy rules and support vector machines (SVMs). Structure identification is realised by an on-line SVM technique, the fuzzy rules are generated automatically. Time-varying learning rates are applied for updating the membership functions of the fuzzy rules. Finally, the upper bounds of the modelling errors are proven.  相似文献   

18.
In this paper, we propose to reinforce the Self-Training strategy in semi-supervised mode by using a generative classifier that may help to train the main discriminative classifier to label the unlabeled data. We call this semi-supervised strategy Help-Training and apply it to training kernel machine classifiers as support vector machines (SVMs) and as least squares support vector machines. In addition, we propose a model selection strategy for semi-supervised training. Experimental results on both artificial and real problems demonstrate that Help-Training outperforms significantly the standard Self-Training. Moreover, compared to other semi-supervised methods developed for SVMs, our Help-Training strategy often gives the lowest error rate.  相似文献   

19.
In this paper, we propose a novel nonparallel classifier, named sparse nonparallel support vector machine (SNSVM), for binary classification. Different with the existing nonparallel classifiers, such as the twin support vector machines (TWSVMs), SNSVM has several advantages: It constructs two convex quadratic programming problems for both linear and nonlinear cases, which can be solved efficiently by successive overrelaxation technique; it does not need to compute the inverse matrices any more before training; it has the similar sparseness with standard SVMs; it degenerates to the TWSVMs when the parameters are appropriately chosen. Therefore, SNSVM is certainly superior to them theoretically. Experimental results on lots of data sets show the effectiveness of our method in both sparseness and classification accuracy and, therefore, confirm the above conclusions further.  相似文献   

20.
为了提高图像标注系统的精度和效率,提出了基于遗传特征选择和支持向量机的图像标注方法。该方法从多媒体描述接口(MPEG-7)标准中抽取图像的视觉特征,采用双编码遗传算法从MPEG-7标准中选择最优的加权特征子集,并训练支持向量机分类器用于图像标注,支持向量机分类器采用多数投票机制。对2 000幅Corel图像的标注结果表明:该方法可以获得最优的加权特征子集,提高了图像标注系统的精度和效率。  相似文献   

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