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1.
针对英文情感分类问题,对不同样本采用不同权重,通过引入模糊隶属度函数,通过计算样本模糊隶属度确定样本隶属某一类程度的模糊支持向量机分类算法,通过对比选取不同核函数和不同惩罚系数的结果.仿真实验结果表明应用模糊支持向量机进行英文情感分类具有较好的分类能力和较高的识别能力.  相似文献   

2.
本文提出了基于支持向量回归机(SVR)的一种新分类算法.它和标准的支持向量机(SVM)不同:标准的支持向量机(SVM)采用固定的模度量间隔且最优化问题与参数有关.本文中我们可以用任意模度量间隔,得到的最优化问题是无参数的线性规划问题,避免了参数选择.数值试验表明了该算法的有效性.  相似文献   

3.
<正>几何问题中,我们常见一类经典问题——三点共线问题.通过学习平面向量知识,我们深刻地体会到:求解三点共线问题,向量的知识和方法非常有用.我们应该学会应用平面向量的有关知识和方法灵活求解几何问题.  相似文献   

4.
标准支持向量机(SVM)抗噪声能力不强,当训练样本中存在有噪声或者野点时,会影响最优分类面的产生,最终导致分类结果出现偏差。针对这一问题,提出了一种考虑最小包围球的加权支持向量机(WSVM),给每个样本点赋予不同的权值,以此来降低噪声或野点对分类结果的影响。对江汉油田某区块的oilsk81,oilsk83和oilsk85三口油井的测井数据进行交叉验证,其中核函数采用了线性、指数和RBF这3种不同的核函数。测试结果显示,无论是在SVM还是在WSVM中,核函数选择RBF识别率都是最高的,同时提出的WSVM不受核函数的影响,识别稳定性好,且在交叉验证中识别率都能够达到100%。  相似文献   

5.
在一些涉及到共起点且终点共线的三个向量之间的关系的问题时,我们可以巧妙利用定比分点向量公式的特点,使这一类问题得以简捷快速的解决.本文通过举例来说明.  相似文献   

6.
支持向量机回归方法在地表水水质评价中的应用   总被引:2,自引:0,他引:2  
将支持向量机方法应用于地表水质评价问题中,建立了多指标水质综合评价的支持向量机回归模型.在地表水质评价标准的基础上采用内插法获得学习样本,经过训练,得到水质评价的分类区间;然后以实测资料对所建模型进行检验,研究结果表明,支持向量机回归模型性能良好、预测精度高、简便易行,是水质评价的一种有效方法,具有广阔的应用前景.  相似文献   

7.
为了减少求支持向量过程中二次规划的复杂度,利用训练样本集的几何信息,选出两类中离另一类最近的边界向量集合,它是样本中最有可能成为支持向量的一部分,用它代替原样本集进行训练.对新增样本,若存在违反KKT条件的样本,只对这部分新样本进行学习.同时找出原样本中可能转化为支持向量的非支持向量样本.基于分析结果,提出了一种新的基于最近边界向量的增量式支持向量机学习算法.对标准数据集的实验结果表明,算法是可行的,有效的.  相似文献   

8.
根据基于支持向量回归机的交通状态短时预测方法建立了数学模型,考虑以交通检测器收集到所要预测时刻前几个时段及被测路段上下游前几时段的交通流量、车道占有率、平均线速度等交通参数为输入,以对应时段的平均线速度为输出.选取核函数,对支持向量回归机进行训练.应用训练完成的支持向量回归机,利用输入参数预测下时段的交通线速度.最后,以北京市北四环某路段的实时监测数据来对模型进行检测,预测结果表明了模型的有效性.  相似文献   

9.
基于非平衡数据集的支持向量域分类模型,提出了一种银行客户个人信用预测方法.首先分析了信用预测的主要方法及其不足,然后研究了支持向量域分类模型及其参数的非负二次规划乘性更新算法,进而提出基于支持向量域分类模型的银行客户个人信用预测方法,最后使用人工数据和实际数据对提出方法与支持向量机预测方法进行对比实验.实验结果表明对于银行客户个人信用预测的非平衡数据分析问题,基于支持向量域模型的分类预测方法更有效.  相似文献   

10.
针对不同类别样本数差异和不同误分代价的分类问题,提出了一种基于最小二乘加权支持向量机的分类预测方法。在最小二乘加权支持向量机的基础上,考虑不同类别样本数差异和不同误分代价,提出了新的最小二乘加权支持向量机分类模型,构造了新的最优分类函数。将该模型应用于个人信用预测实验,与已有方法的对比实验结果表明,提出的模型在解决不同类别样本数差异和不同误分代价的个人信用预测问题时,有效地降低了总误分代价,提高了个人信用预测精确度。  相似文献   

11.
加权线性支持向量分类机是数据挖掘的新方法.它对应于一个优化问题.针对加权线性支持向量分类机优化问题建立了数据扰动分析理论方法.具体地针对加权线性支持向量分类机的原始问题建立了数据扰动分析基本定理,定理可以得到加权线性支持向量分类机问题的解及决策函数对数据参数的偏导数,同时可以定量分析输入数据的误差以及数据各种变化对其解以及决策函数值的定量影响,可以回答加权线性支持向量分类机问题的稳定性问题和灵敏度分析问题.  相似文献   

12.
In this article, the assessment of new coordinated design of power system stabilizers (PSSs) and static var compensator (SVC) in a multimachine power system via statistical method is proposed. The coordinated design problem of PSSs and SVC over a wide range of loading conditions is handled as an optimization problem. The bacterial swarming optimization (BSO), which synergistically couples the bacterial foraging with the particle swarm optimization (PSO), is used to seek for optimal controllers parameters. By minimizing the proposed objective function, in which the speed deviations between generators are involved; stability performance of the system is enhanced. To compare the capability of PSS and SVC, both are designed independently, and then in a coordinated manner. Simultaneous tuning of the BSO‐based coordinated controller gives robust damping performance over wide range of operating conditions and large disturbance in compare to optimized PSS controller based on BSO (BSOPSS) and optimized SVC controller based on BSO (BSOSVC). Moreover, a statistical T test is executed to validate the robustness of coordinated controller versus uncoordinated one. © 2014 Wiley Periodicals, Inc. Complexity 21: 256–266, 2015  相似文献   

13.
在K-SVCR算法结构的基础上构造了新的模型.模型的特点是它的一阶最优化条件可以转化为一个线性互补问题,通过Lagrangian隐含数,可以将其进一步转化成一个强凸的无约束优化问题.利用共轭梯度技术对其进行求解,在有限步内得到分类超平面.最后在标准数据集进行了初步试验.试验结果显示了提出的算法在分类的精度和速度上都有明显提高.  相似文献   

14.
Multiclass classification and probability estimation have important applications in data analytics. Support vector machines (SVMs) have shown great success in various real-world problems due to their high classification accuracy. However, one main limitation of standard SVMs is that they do not provide class probability estimates, and thus fail to offer uncertainty measure about class prediction. In this article, we propose a simple yet effective framework to endow kernel SVMs with the feature of multiclass probability estimation. The new probability estimator does not rely on any parametric assumption on the data distribution, therefore, it is flexible and robust. Theoretically, we show that the proposed estimator is asymptotically consistent. Computationally, the new procedure can be conveniently implemented using standard SVM softwares. Our extensive numerical studies demonstrate competitive performance of the new estimator when compared with existing methods such as multiple logistic regression, linear discrimination analysis, tree-based methods, and random forest, under various classification settings. Supplementary materials for this article are available online.  相似文献   

15.
We consider two-dimensional rectangular strip packing without rotation of items and without the guillotine cutting constraint. We propose two iterative heuristics. The first one, SVC(SubKP), is based on a single-pass heuristic SubKP which fills every most bottom-left free space in a one-dimensional knapsack fashion, that is, considering only item widths. It appears especially important to assign suitable ‘pseudo-profits’ in this knapsack problem. The second heuristic BS(BLR) is based on the known randomized framework Bubble-Search. It generates different item sequences and runs a new sequence-based heuristic Bottom-Left-Right (BLR), a simple modification of the Bottom-Left heuristic. We investigate the solution sets of SubKP and BLR and their relation to each other. In the tests, SVC(SubKP) improves the results for larger instances of the waste-free classes of Hopper and Turton and, on average, for the tested non-waste-free classes, compared to the latest literature. BS(BLR) gives the best results in some classes with smaller number of items (20,40).  相似文献   

16.
Multicategory Classification by Support Vector Machines   总被引:8,自引:0,他引:8  
We examine the problem of how to discriminate between objects of three or more classes. Specifically, we investigate how two-class discrimination methods can be extended to the multiclass case. We show how the linear programming (LP) approaches based on the work of Mangasarian and quadratic programming (QP) approaches based on Vapnik's Support Vector Machine (SVM) can be combined to yield two new approaches to the multiclass problem. In LP multiclass discrimination, a single linear program is used to construct a piecewise-linear classification function. In our proposed multiclass SVM method, a single quadratic program is used to construct a piecewise-nonlinear classification function. Each piece of this function can take the form of a polynomial, a radial basis function, or even a neural network. For the k > 2-class problems, the SVM method as originally proposed required the construction of a two-class SVM to separate each class from the remaining classes. Similarily, k two-class linear programs can be used for the multiclass problem. We performed an empirical study of the original LP method, the proposed k LP method, the proposed single QP method and the original k QP methods. We discuss the advantages and disadvantages of each approach.  相似文献   

17.
AHP判断矩阵权向量的改进最小二乘求解   总被引:1,自引:0,他引:1  
提出了基于最小二乘法计算判断矩阵权向量的新方法.固定AHP判断矩阵权向量中的一个值为常量,利用判断矩阵的上三角部分元素,设计了一种计算判断矩阵权向量的新算法,算法简单,计算容易,与特征向量排序方法导出标度相同,并且能够证明存在唯一解.实验表明该算法具有有效性和可行性.  相似文献   

18.
The widely used Support Vector Machine (SVM) method has shown to yield good results in Supervised Classification problems. When the interpretability is an important issue, then classification methods such as Classification and Regression Trees (CART) might be more attractive, since they are designed to detect the important predictor variables and, for each predictor variable, the critical values which are most relevant for classification. However, when interactions between variables strongly affect the class membership, CART may yield misleading information. Extending previous work of the authors, in this paper an SVM-based method is introduced. The numerical experiments reported show that our method is competitive against SVM and CART in terms of misclassification rates, and, at the same time, is able to detect critical values and variables interactions which are relevant for classification.  相似文献   

19.
An algorithm for selecting features in the classification learning problem is considered. The algorithm is based on a modification of the standard criterion used in the support vector machine method. The new criterion adds to the standard criterion a penalty function that depends on the selected features. The solution of the problem is reduced to finding the minimax of a convex-concave function. As a result, the initial set of features is decomposed into three classes—unconditionally selected, weighted selected, and eliminated features. Original Russian Text Yu.V. Goncharov, I.B. Muchnik, L.V. Shvartser @, 2008, published in Zhurnal Vychislitel’noi Matematiki i Matematicheskoi Fiziki, 2008, Vol. 48, No. 7, pp. 1318–1336.  相似文献   

20.
现代战斗机空战是当前空中力量遂行作战任务的主要模式,其空战效能的评估问题也是研究的难点之一.在分析现代战斗机空战模式及七个关键影响因素的基础上,引入人工智能技术的思路和方法,运用LS-SVM支持向量机方法对现代战斗机空战效能进行了多级评估LS-SVM支持向量机分类器设计并建立智能评估模型,结合实例进行了计算和分析,为进一步研究空战效能的评估问题提供了一种新的思路.  相似文献   

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