首页机械学
0


部分可观测的最大熵辨别马尔可夫网络

Partially Observed Maximum Entropy Discrimination Markov Networks
课程网址: http://videolectures.net/cmulls08_zhu_pome/  
主讲教师: Jun Zhu
开课单位: 卡内基梅隆大学
开课时间: 2009-01-15
课程语种: 英语
中文简介:
学习带有隐藏变量的图形模型可以为复杂数据提供语义洞察,并在不依赖昂贵的、有时无法完全注释的训练数据的情况下产生显著的结构化预测因子。虽然基于可能性的方法已经被广泛探索,但据我们所知,学习基于最大边际原则的具有潜在变量的结构化预测模型仍然是一个很大程度上开放的问题。本文提出了一个部分观测的最大熵鉴别马尔可夫网络模型(POMEN),该模型试图结合贝叶斯模型和基于边缘的模型的优点,从部分标记的数据中学习马尔可夫网络。Pomen提出了一个平均预测规则,它类似于Bayes预测,对过度拟合更为稳健,但也建立在与M$^3$N相似的理想判别律之上。我们开发了一种EM型算法,利用现有的M$^3$N凸优化算法作为子例程。我们在现实的Web数据提取任务中展示了POMEN相对于现有方法的出色性能。
课程简介: Learning graphical models with hidden variables can offer semantic insights to complex data and lead to salient structured predictors without relying on expensive, sometime unattainable fully annotated training data. While likelihood-based methods have been extensively explored, to our knowledge, learning structured prediction models with latent variables based on the max-margin principle remains largely an open problem. In this paper, we present a partially observed Maximum Entropy Discrimination Markov Network (PoMEN) model that attempts to combine the advantages of Bayesian and margin based paradigms for learning Markov networks from partially labeled data. PoMEN leads to an averaging prediction rule that resembles a Bayes predictor that is more robust to overfitting, but is also built on the desirable discriminative laws resemble those of the M$^3$N. We develop an EM-style algorithm utilizing existing convex optimization algorithms for M$^3$N as a subroutine. We demonstrate competent performance of PoMEN over existing methods on a real-world web data extraction task.
关 键 词: 计算机科学; 机械学习; 马尔科夫过程
课程来源: 视频讲座网
最后编审: 2020-06-22:chenxin
阅读次数: 42