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用于多视图学习和流形协调的RKHS

An RKHS for Multi-View Learning and Manifold Co-Regularization
课程网址: http://videolectures.net/icml08_rosenberg_rkhs/  
主讲教师: David S. Rosenberg
开课单位: 加州大学伯克利分校
开课时间: 2008-08-06
课程语种: 英语
中文简介:
受co训练的启发,许多多视图半监督核方法实现了以下思想:在多个再生核Hilbert空间(RKHS)的每一个中找到一个函数,使得(a)所选择的函数对未标记的示例做出类似的预测,以及(b)由所选函数给出的平均预测在标记的示例上表现良好。在本文中,我们构建了一个单一的RKHS,其具有依赖于数据的“协同正规化”规范,从而减少了这些标准监督学习的方法。该RKHS的再现内核可以明确地导出并插入到任何内核方法中,从而大大扩展了协同正规化的理论和算法范围。特别是,随着这种发展,Rouredmacher在(Rosenberg&Bartlett,2007)中给出的共正则化的复杂性很容易从众所周知的结果中得出。此外,还可以轻松应用由局部Rademacher复杂性给出的更精细的界限。我们提出了基于协同正则化的算法替代流形正则化(Belkin等,2006; Sindhwani等,2005a),这导致对半监督任务的主要经验改进。与最近提出的转换方法(Yu et al。,2008)不同,我们的RKHS公式实际上是半监督的,并且自然地延伸到看不见的测试数据。
课程简介: Inspired by co-training, many multi-view semi-supervised kernel methods implement the following idea: find a function in each of multiple Reproducing Kernel Hilbert Spaces (RKHSs) such that (a) the chosen functions make similar predictions on unlabeled examples, and (b) the average prediction given by the chosen functions performs well on labeled examples. In this paper, we construct a single RKHS with a data-dependent “co-regularization” norm that reduces these approaches to standard supervised learning. The reproducing kernel for this RKHS can be explicitly derived and plugged into any kernel method, greatly extending the theoretical and algorithmic scope of co-regularization. In particular, with this development, the Rademacher complexity bound for co-regularization given in (Rosenberg & Bartlett, 2007) follows easily from well-known results. Furthermore, more refined bounds given by localized Rademacher complexity can also be easily applied. We propose a co-regularization based algorithmic alternative to manifold regularization (Belkin et al., 2006; Sindhwani et al., 2005a) that leads to major empirical improvements on semi-supervised tasks. Unlike the recently proposed transductive approach of (Yu et al., 2008), our RKHS formulation is truly semi-supervised and naturally extends to unseen test data.
关 键 词: 半监督核方法; 协同正规化; 流形正则化
课程来源: 视频讲座网
最后编审: 2019-04-21:lxf
阅读次数: 42