论文标题
改进的自适应算法,用于可扩展的主动学习和弱标签
Improved Adaptive Algorithm for Scalable Active Learning with Weak Labeler
论文作者
论文摘要
具有强大和弱标签者的积极学习考虑了一个实用的环境,在该环境中,我们可以访问弱标签者提供的代价高昂但准确的强标签和不准确但便宜的预测。我们在流式设置中研究了这个问题,必须在其中做出\ textit {在线}。我们设计了一种新型的算法模板,弱标记器活动覆盖物(WL-AC),能够坚固地利用较低质量的弱标签来降低查询复杂性,同时保持所需的准确性水平。访问弱标签者的积极学习算法会学习一个差异分类器,该分类器预测弱标签与强标签不同的位置;这需要对差异分类器的可实现性的强烈假设(Zhang and Chaudhuri,2015年)。 WL-AC绕过此\ textIt {可实现性}假设,因此适用于许多真实的场景,例如随机损坏的弱标签和高维分类器的高维家族(\ textit {efextit {e.g。,}深神经网)。此外,WL-AC通过对弱标签的全面开发来巧妙地进行评估质量,这允许将任何活跃的学习策略转换为可以利用弱标签者的质量。我们提供了此模板的实例化,该模板可为任何给定的弱标签达到最佳查询复杂性,而不知道其准确性A-Priori。从经验上讲,我们提出了WL-AC模板的实例化,该模板可以有效地用于大规模模型(\ textit {例如,深神经网),并通过显着减少标签的数量,同时保持与被动学习的准确性相同的准确性,并显示出对损坏的数据集的有效性。
Active learning with strong and weak labelers considers a practical setting where we have access to both costly but accurate strong labelers and inaccurate but cheap predictions provided by weak labelers. We study this problem in the streaming setting, where decisions must be taken \textit{online}. We design a novel algorithmic template, Weak Labeler Active Cover (WL-AC), that is able to robustly leverage the lower quality weak labelers to reduce the query complexity while retaining the desired level of accuracy. Prior active learning algorithms with access to weak labelers learn a difference classifier which predicts where the weak labels differ from strong labelers; this requires the strong assumption of realizability of the difference classifier (Zhang and Chaudhuri,2015). WL-AC bypasses this \textit{realizability} assumption and thus is applicable to many real-world scenarios such as random corrupted weak labels and high dimensional family of difference classifiers (\textit{e.g.,} deep neural nets). Moreover, WL-AC cleverly trades off evaluating the quality with full exploitation of weak labelers, which allows to convert any active learning strategy to one that can leverage weak labelers. We provide an instantiation of this template that achieves the optimal query complexity for any given weak labeler, without knowing its accuracy a-priori. Empirically, we propose an instantiation of the WL-AC template that can be efficiently implemented for large-scale models (\textit{e.g}., deep neural nets) and show its effectiveness on the corrupted-MNIST dataset by significantly reducing the number of labels while keeping the same accuracy as in passive learning.