论文标题

renyicl:偏斜renyi差异的对比表示学习

RenyiCL: Contrastive Representation Learning with Skew Renyi Divergence

论文作者

Lee, Kyungmin, Shin, Jinwoo

论文摘要

对比表示学习试图通过估计数据的多个视图之间的共享信息来获得有用的表示形式。在这里,数据增强的选择对学会表示的质量很敏感:随着更难的应用,数据增加了,视图共享更多与任务相关的信息,但也可以限制任务限制的信息,从而阻碍表示代表的概括能力。在此激励的情况下,我们提出了一种新的强大的对比学习计划,即rényicl,可以通过利用RényiDivergence有效地管理更艰难的增强。我们的方法建立在RényiDivergence的各种下限基础上,但是由于差异很大,对变异方法的幼稚用法是不切实际的。为了应对这一挑战,我们提出了一个新颖的对比目标,该目标对偏斜的差异进行了变化估计,并提供了理论上的保证,可以保证偏斜分歧的变异估计如何导致稳定的训练。我们表明,Rényi对比学习目标同时执行先天硬性负面抽样和易于正面抽样,以便它可以选择性地学习有用的功能并忽略滋扰功能。通过对Imagenet的实验,我们表明Rényi对比学习和更强的增强性学习优于其他自我监督的方法,而没有额外的正则化或计算开销。此外,我们还验证了我们在图形和表格等其他领域的方法,显示了与其他对比方法相比的经验增益。

Contrastive representation learning seeks to acquire useful representations by estimating the shared information between multiple views of data. Here, the choice of data augmentation is sensitive to the quality of learned representations: as harder the data augmentations are applied, the views share more task-relevant information, but also task-irrelevant one that can hinder the generalization capability of representation. Motivated by this, we present a new robust contrastive learning scheme, coined RényiCL, which can effectively manage harder augmentations by utilizing Rényi divergence. Our method is built upon the variational lower bound of Rényi divergence, but a naïve usage of a variational method is impractical due to the large variance. To tackle this challenge, we propose a novel contrastive objective that conducts variational estimation of a skew Rényi divergence and provide a theoretical guarantee on how variational estimation of skew divergence leads to stable training. We show that Rényi contrastive learning objectives perform innate hard negative sampling and easy positive sampling simultaneously so that it can selectively learn useful features and ignore nuisance features. Through experiments on ImageNet, we show that Rényi contrastive learning with stronger augmentations outperforms other self-supervised methods without extra regularization or computational overhead. Moreover, we also validate our method on other domains such as graph and tabular, showing empirical gain over other contrastive methods.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源