arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1504.05035cs.LGcs.CV
收藏

F-SVM:通过凸松弛将特征变换和SVM学习结合起来

F-SVM: Combination of Feature Transformation and SVM Learning via Convex Relaxation

Harbin Institute of Technology(哈尔滨工业大学);Sun Yat-sen University(中山大学)

Xiaohe Wu, Wangmeng Zuo, Yuanyuan Zhu, Liang Lin

摘要:

支持向量机(SVM)的泛化误差界取决于半径和间隔的比值,而标准SVM只考虑了间隔的最大化而忽略了半径的最小化。提出了几种方法来集成半径和间隔的特征变换和SVM分类器的联合学习。然而,它们中的大多数要么要求变换矩阵的形式是对角的,要么是非凸的且计算量大。本文提出了一种新的特征空间最小包围球(MEB)半径的近似方法,并在此基础上提出了一种基于凸半径-边缘的SVM模型,用于特征变换和SVM分类器的联合学习,即,F-SVM采用交替最小化方法求解F-SVM模型,通过梯度下降更新特征变换,利用已有的SVM求解器更新分类器。通过与核主成分分析相结合,F-SVM被进一步扩展为非线性变换和分类器的联合学习。在UCI机器学习数据集和LFW人脸数据集上的实验结果表明,F-SVM的性能优于标准SVM和现有的基于半径边缘的SVM,例如,RMM、R-SVM+和R-SVM+μ。

英文摘要:

The generalization error bound of support vector machine (SVM) depends on the ratio of radius and margin, while standard SVM only considers the maximization of the margin but ignores the minimization of the radius. Several approaches have been proposed to integrate radius and margin for joint learning of feature transformation and SVM classifier. However, most of them either require the form of the transformation matrix to be diagonal, or are non-convex and computationally expensive. In this paper, we suggest a novel approximation for the radius of minimum enclosing ball (MEB) in feature space, and then propose a convex radius-margin based SVM model for joint learning of feature transformation and SVM classifier, i.e., F-SVM. An alternating minimization method is adopted to solve the F-SVM model, where the feature transformation is updatedvia gradient descent and the classifier is updated by employing the existing SVM solver. By incorporating with kernel principal component analysis, F-SVM is further extended for joint learning of nonlinear transformation and classifier. Experimental results on the UCI machine learning datasets and the LFW face datasets show that F-SVM outperforms the standard SVM and the existing radius-margin based SVMs, e.g., RMM, R-SVM+ and R-SVM+μ.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑