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使用图形处理器进行大规模深度无监督学习

Large-Scale Deep Unsupervised Learning Using Graphics Processors
课程网址: http://videolectures.net/icml09_raina_lsd/  
主讲教师: Rajat Raina
开课单位: 斯坦福大学
开课时间: 2009-08-26
课程语种: 英语
中文简介:
无监督学习方法的前景是它们有可能使用大量未标记数据来学习具有数百万个自由参数的复杂,非线性模型。我们考虑两个众所周知的无监督学习模型,深信念网络(DBN)和稀疏编码,最近已应用于一系列机器学习应用(Hinton&Salakhutdinov,2006; Raina等,2007)。不幸的是,两种模型的当前学习算法都适用于大规模应用,迫使研究人员专注于较小规模的模型,或者使用较少的训练样例。在本文中,我们建议采用大规模并行方法来帮助解决这些问题。我们认为现代图形处理器远远超过了多种CPU的计算能力,并有可能重新调整深度无监督学习方法的适用性。我们开发了使用图形处理器大规模并行化无监督学习任务的通用原则。我们证明这些原理可以应用于成功扩展DBN和稀疏编码的学习算法。我们的DBN学习实现比大型模型的双核CPU实现快70倍。例如,我们能够减少从几周到单个周期内学习具有1亿个免费参数的层DBN所需的时间。对于稀疏编码,我们开发了一种简单的,固有的并行算法,与以前的方法相比,可以节省5到15倍的速度。
课程简介: The promise of unsupervised learning methods lies in their potential to use vast amounts of unlabeled data to learn complex, highly nonlinear models with millions of free parameters. We consider two well-known unsupervised learning models, deep belief networks (DBNs) and sparse coding, that have recently been applied to a flurry of machine learning applications (Hinton & Salakhutdinov, 2006; Raina et al., 2007). Unfortunately, current learning algorithms for both models are too slow for large-scale applications, forcing researchers to focus on smaller-scale models, or to use fewer training examples. In this paper, we suggest massively parallel methods to help resolve these problems. We argue that modern graphics processors far surpass the computational capabilities of multicore CPUs, and have the potential to revolutionize the applicability of deep unsupervised learning methods. We develop general principles for massively parallelizing unsupervised learning tasks using graphics processors. We show that these principles can be applied to successfully scaling up learning algorithms for both DBNs and sparse coding. Our implementation of DBN learning is up to 70 times faster than a dual-core CPU implementation for large models. For example, we are able to reduce the time required to learn a four-layer DBN with 100 million free parameters from several weeks to around a single day. For sparse coding, we develop a simple, inherently parallel algorithm, that leads to a 5 to 15-fold speedup over previous methods.
关 键 词: 无监督学习方法; 非线性模型; 稀疏编码
课程来源: 视频讲座网
最后编审: 2019-04-24:lxf
阅读次数: 26