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主动和半监督数据域描述

Active and Semi-Supervised Data Domain Description
课程网址: http://videolectures.net/ecmlpkdd09_brefeld_assddd/  
主讲教师: Ulf Brefeld
开课单位: 莱芬娜大学
开课时间: 2009-10-20
课程语种: 英语
中文简介:
数据域描述技术旨在导出属于感兴趣类别的对象的简明描述。例如,支持向量域描述(SVDD)学习包含大量提供的未标记数据的超球面,使得位于球外的点被认为是异常的。但是,在无人监督的环境中,专家和背景知识等相关信息仍未使用。在本文中,我们将数据域描述重新描述为半监督学习任务,即,我们提出了数据域描述的半监督泛化(SSSVDD)来处理未标记和标记的示例。相应的优化问题是非凸的。我们将其转化为无约束的连续问题,可以通过基于梯度的技术进行精确优化。此外,我们设计了一种有效的主动学习策略来查询低置信度观察。我们对网络入侵检测和对象识别任务的实证评估表明,我们的SSSVDD在相关学习环境中始终优于基线方法。
课程简介: Data domain description techniques aim at deriving concise descriptions of objects belonging to a category of interest. For instance, the support vector domain description (SVDD) learns a hypersphere enclosing the bulk of provided unlabeled data such that points lying outside of the ball are considered anomalous. However, relevant information such as expert and background knowledge remain unused in the unsupervised setting. In this paper, we rephrase data domain description as a semi-supervised learning task, that is, we propose a semi-supervised generalization of data domain description (SSSVDD) to process unlabeled and labeled examples. The corresponding optimization problem is non-convex. We translate it into an unconstraint, continuous problem that can be optimized accurately by gradient-based techniques. Furthermore, we devise an effective active learning strategy to query low-confidence observations. Our empirical evaluation on network intrusion detection and object recognition tasks shows that our SSSVDDs consistently outperform baseline methods in relevant learning settings.
关 键 词: 数据域描述; 超球面; 半监督学习
课程来源: 视频讲座网
最后编审: 2019-03-24:cwx
阅读次数: 35