摘要
支持向量机是机器学习中一种非常重要的分类方法,它在文本分类、语音识别、图像分析、信息安全等诸多领域均有重要的应用.提出了基于支持向量机对偶问题的一种非精确增广拉格朗日算法,讨论了所提算法的收敛性结果,并利用支持向量机模型的稀疏特性,结合矩阵不完全Cholesky分解以及Sherman-Morrison-Woodbury公式等程序实现技巧,极大地减少了所提算法的时间与空间复杂度.数值结果验证了提出算法的可行性和高效性.
Support vector machine is one of important classification methods in machine learning,which has important applications in varieties of fields,including text classification,speech recognition,image analysis,information security,and so on.This paper proposes an inexact augmented Lagrangian method for the dual problem of support vector machine,and carries out the analysis on convergence of the proposed algorithm.Based on the sparse property of support vector machines and some implementation techniques such as incomplete Cholesky decomposition and Sherman-MorrisonWoodbury formula,the complexities of time and space of our proposed algorithm are greatly reduced.Numerical experiments verify the feasibility and high efficiency of the proposed algorithm.
引文
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