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论深层信念网络的定量分析

On the Quantitative Analysis of Deep Belief Networks
课程网址: http://videolectures.net/icml08_salakhutdinov_qadb/  
主讲教师: Ruslan Salakhutdinov
开课单位: 卡内基梅隆大学
开课时间: 2008-07-29
课程语种: 英语
中文简介:
Deep Belief Networks(DBN)是包含许多隐藏变量层的生成模型。用于学习和近似推理的高效贪心算法使这些模型能够在许多应用领域中成功应用。 DBN的主要构建块是一个称为受限玻尔兹曼机(RBM)的二分无向图形模型。由于存在分区功能,RBM中的模型选择,复杂性控制和精确的最大似然学习是难以处理的。退火重要性采样(AIS)可用于有效地估计RBM的分区功能。我们提出了一种新的AIS方案,用于比较RBM与不同架构。我们进一步展示了如何使用AIS估计器以及近似推断来估计具有多个隐藏层的DBN模型分配给测试数据的对数概率的下限。据我们所知,这是获得定量结果的第一步,这将使我们能够直接评估深度信念网络作为数据生成模型的表现。
课程简介: Deep Belief Networks (DBN's) are generative models that contain many layers of hidden variables. Efficient greedy algorithms for learning and approximate inference have allowed these models to be applied successfully in many application domains. The main building block of a DBN is a bipartite undirected graphical model called a restricted Boltzmann machine (RBM). Due to the presence of the partition function, model selection, complexity control, and exact maximum likelihood learning in RBM's are intractable. Annealed Importance Sampling (AIS), can be used to efficiently estimate the partition function of an RBM. We present a novel AIS scheme for comparing RBM's with different architectures. We further show how an AIS estimator, along with approximate inference, can be used to estimate a lower bound on the log-probability that a DBN model with multiple hidden layers assigns to the test data. This is, to our knowledge, the first step towards obtaining quantitative results that would allow us to directly assess the performance of Deep Belief Networks as generative models of data.
关 键 词: 隐藏变量层; 高效贪心算法; 概率
课程来源: 视频讲座网
最后编审: 2020-06-22:chenxin
阅读次数: 58