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基于奇异值投影的保秩最小化

Guaranteed Rank Minimization via Singular Value Projection
课程网址: http://videolectures.net/nips2010_jain_grm/  
主讲教师: Prateek Jain
开课单位: Nuance通讯公司
开课时间: 2011-03-25
课程语种: 英语
中文简介:
最小化受仿射约束的矩阵的等级是机器学习和统计中的许多重要应用的基本问题。在本文中,我们提出了一种简单快速的算法SVP(奇异值投影),用于在仿射约束ARMP下进行秩最小化,并表明SVP恢复了满足受限等距属性}(RIP)的仿射约束的最小秩解。我们的方法即使在存在噪声的情况下也能保证几何收敛速度,并且需要对RIP常数进行严格的假设,而不是现有方法。我们还为我们的SVP框架引入了牛顿步骤,以通过大量的经验收益加速收敛。接下来,我们针对ARMP的一个实际重要的应用解决了低秩矩阵完成的问题,其中定义的仿射约束不直接服从RIP,因此SVP的保证不成立。然而,我们通过显示更受限制的等距属性并且凭经验观察我们的算法从几乎最佳数量的均匀采样条目中恢复低秩非相干矩阵,为我们的算法的精确恢复的证明提供了部分进展。我们还凭经验证明,我们的算法优于现有方法,例如{caiCS2008,LeeB2009b,KeshavanOM2009},ARMP和矩阵完成问题的数量级,并且对噪声和采样方案也更加稳健。特别是,结果表明,我们的SVP牛顿方法对噪声具有显着的鲁棒性,并且在矩阵完成问题的更逼真的幂律采样方案上表现出色。
课程简介: Minimizing the rank of a matrix subject to affine constraints is a fundamental problem with many important applications in machine learning and statistics. In this paper we propose a simple and fast algorithm SVP (Singular Value Projection) for rank minimization under affine constraints ARMP and show that SVP recovers the minimum rank solution for affine constraints that satisfy a Restricted Isometry Property} (RIP). Our method guarantees geometric convergence rate even in the presence of noise and requires strictly weaker assumptions on the RIP constants than the existing methods. We also introduce a Newton-step for our SVP framework to speed-up the convergence with substantial empirical gains. Next, we address a practically important application of ARMP - the problem of low-rank matrix completion, for which the defining affine constraints do not directly obey RIP, hence the guarantees of SVP do not hold. However, we provide partial progress towards a proof of exact recovery for our algorithm by showing a more restricted isometry property and observe empirically that our algorithm recovers low-rank Incoherent matrices from an almost optimal number of uniformly sampled entries. We also demonstrate empirically that our algorithms outperform existing methods, such as those of \cite{CaiCS2008,LeeB2009b, KeshavanOM2009}, for ARMP and the matrix completion problem by an order of magnitude and are also more robust to noise and sampling schemes. In particular, results show that our SVP-Newton method is significantly robust to noise and performs impressively on a more realistic power-law sampling scheme for the matrix completion problem.
关 键 词: 机器学习; 受仿射约束; 奇异值投影
课程来源: 视频讲座网
最后编审: 2019-07-25:cwx
阅读次数: 123