论文标题
不变代表学习中的基本限制和权衡
Fundamental Limits and Tradeoffs in Invariant Representation Learning
论文作者
论文摘要
广泛的机器学习应用程序,例如保护隐私学习,算法公平性和域的适应/泛化等,涉及数据的不变性表示,旨在实现两个竞争目标:(a)最大程度地提高目标响应的信息或准确性,以及(b)最大程度地与公平的protection of Protection,E。e.G(b)最大程度地提高不公正或独立性。尽管它们的适用性广泛,但对于准确性和不变性,对最佳权衡方面的理论理解仍然严重缺乏。在本文中,我们在分类和回归设置下提供了此类权衡的信息理论分析。更确切地说,我们提供了通过数据的任何表示可以实现的准确性和不变性的几何表征。我们将这个可行区域称为信息平面。我们为分类情况提供了一个可行区域的内部结合,并为回归案例提供了精确的表征,这使我们能够在精度和不变性之间绑定或精确地表征帕累托最佳边界。尽管我们的贡献主要是理论上的,但我们的结果的关键实际应用是证明任何给定表示算法的潜在次级临时性,用于分类或回归任务。我们的结果为准确性和不变性之间的基本相互作用提供了新的启示,并且可能有助于指导未来代表性学习算法的设计。
A wide range of machine learning applications such as privacy-preserving learning, algorithmic fairness, and domain adaptation/generalization among others, involve learning invariant representations of the data that aim to achieve two competing goals: (a) maximize information or accuracy with respect to a target response, and (b) maximize invariance or independence with respect to a set of protected features (e.g., for fairness, privacy, etc). Despite their wide applicability, theoretical understanding of the optimal tradeoffs -- with respect to accuracy, and invariance -- achievable by invariant representations is still severely lacking. In this paper, we provide an information theoretic analysis of such tradeoffs under both classification and regression settings. More precisely, we provide a geometric characterization of the accuracy and invariance achievable by any representation of the data; we term this feasible region the information plane. We provide an inner bound for this feasible region for the classification case, and an exact characterization for the regression case, which allows us to either bound or exactly characterize the Pareto optimal frontier between accuracy and invariance. Although our contributions are mainly theoretical, a key practical application of our results is in certifying the potential sub-optimality of any given representation learning algorithm for either classification or regression tasks. Our results shed new light on the fundamental interplay between accuracy and invariance, and may be useful in guiding the design of future representation learning algorithms.