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PAC-Bayesian分析及其应用

PAC-Bayesian Analysis and Its Applications
课程网址: http://videolectures.net/ecmlpkdd2012_seldin_laviolette_shawe_tay...  
主讲教师: Yevgeny Seldin, John Shawe-Taylor, François Laviolette
开课单位: 哥本哈根大学
开课时间: 2012-10-29
课程语种: 英语
中文简介:
PAC-Bayesian分析是机器学习中数据依赖分析的一种基本且非常通用的工具。到目前为止,它已被应用于监督学习、非监督学习和强化学习等多个领域,产生了最先进的算法和相应的泛化边界。PAC-Bayesian分析从某种意义上说,是将Bayesian方法和PAC学习的最佳结果结合起来:(1)它提供了一种利用先验知识的简便方法(如Bayesian方法);(2)提供严格而明确的泛化保证(如VC理论);(3)它依赖于数据,提供了一种简单而严格的方法来利用良性条件(如Rademacher复杂性)。此外,PAC-Bayesian边界直接导致高效的学习算法。因此,它是机器学习的核心和基础学科。虽然第一批关于PAC-Bayesian分析的论文并不容易阅读,但是后续的简化使其能够在三张幻灯片中逐字解释。我们将从对PAC-Bayesian分析的一般介绍开始,这应该是一个普通的学生,他们熟悉机器学习的基本水平。然后,我们将考察PAC-Bayesian边界的多种形式及其在不同领域的众多应用,包括有监督的an、d无监督学习、有限域和连续域,以及鞅和强化学习的最新扩展。其中一些应用程序将得到更详细的解释,而另一些应用程序将进行高层次的调查。我们还将描述PAC-Bayesian分析、Bayesian学习、VC理论和Rademacher复杂性之间的关系和区别。我们将讨论受贝叶斯分析启发的频域的作用、价值和缺点。
课程简介: PAC-Bayesian analysis is a basic and very general tool for data-dependent analysis in machine learning. By now, it has been applied in such diverse areas as supervised learning, unsupervised learning, and reinforcement learning, leading to state-of-the-art algorithms and accompanying generalization bounds. PAC-Bayesian analysis, in a sense, takes the best out of Bayesian methods and PAC learning and puts it together: (1) it provides an easy way to exploit prior knowledge (like Bayesian methods); (2) it provides strict and explicit generalization guarantees (like VC theory); and (3) it is data-dependent and provides an easy and strict way of exploiting benign conditions (like Rademacher complexities). In addition, PAC-Bayesian bounds directly lead to efficient learning algorithms. Thus, it is a key and basic subject for machine learning. While the first papers on PAC-Bayesian analysis were not easy to readsubsequent simplifications made it possible to explain it literally in three slides. We will start with a general introduction to PAC-Bayesian analysis, which should be accessible to an average student, who is familiar with machine learning at the basic level. Then, we will survey multiple forms of PAC-Bayesian bounds and their numerous applications in different fields, including supervised an, d unsupervised learning, finite and continuous domains, and the very recent extension to martingales and reinforcement learning. Some of these applications will be explained in more details, while others will be surveyed at a high level. We will also describe the relations and distinctions between PAC-Bayesian analysis, Bayesian learning, VC theory, and Rademacher complexities. We will discuss the role, value, and shortcomings of frequentist bounds that are inspired by Bayesian analysis.
关 键 词: 数据简化; 数据依赖分析; PAC-Bayesian边界; 泛化边界; 先验知识; 机器学习
课程来源: 视频讲座网公开课
最后编审: 2019-05-26:cwx
阅读次数: 54