0


基于边距和半径的多核学习

Margin and Radius Based Multiple Kernel Learning
课程网址: http://videolectures.net/ecmlpkdd09_do_mrbmkl/  
主讲教师: Huyen Thi Thanh Do
开课单位: 日内瓦大学
开课时间: 2009-10-20
课程语种: 英语
中文简介:
内核方法和特别是支持向量机(SVM)的一个严重缺点是难以为给定数据集选择合适的内核函数。解决该问题的方法之一是多核学习(MKL),其中几个内核自适应地组合给定数据集。许多现有的MKL方法使用SVM目标函数并尝试找到基本内核的线性组合,使得类之间的分离余量最大化。然而,这些方法忽略了这样一个事实,即理论误差界限不仅取决于边界,还取决于包含所有训练实例的最小球体的半径。我们提出了一种新颖的MKL算法,该算法在考虑边缘和半径的情况下优化误差界限。实证结果表明,该方法与其他现有的MKL方法相比具有优势。
课程简介: A serious drawback of kernel methods, and Support Vector Machines (SVM) in particular, is the difficulty in choosing a suitable kernel function for a given dataset. One of the approaches proposed to address this problem is Multiple Kernel Learning (MKL) in which several kernels are combined adaptively for a given dataset. Many of the existing MKL methods use the SVM objective function and try to find a linear combination of basic kernels such that the separating margin between the classes is maximized. However, these methods ignore the fact that the theoretical error bound depends not only on the margin, but also on the radius of the smallest sphere that contains all the training instances. We present a novel MKL algorithm that optimizes the error bound taking account of both the margin and the radius. The empirical results show that the proposed method compares favorably with other state-of-the-art MKL methods.
关 键 词: 内核方法; 向量机; 给定数据集
课程来源: 视频讲座网
最后编审: 2019-03-24:cwx
阅读次数: 37