论文标题
强大的验证:即使分布变化,也有自信的预测
Robust Validation: Confident Predictions Even When Distributions Shift
论文作者
论文摘要
尽管机器学习和统计数据的传统观点假设培训和测试样本来自同一人群,但实践掩盖了这一小说。因此,一种来自强大的统计和优化的策略是为分配扰动建立一个强大的模型。在本文中,我们采用了另一种方法来描述鲁棒预测推断的过程,其中模型提供了对其预测而不是点预测的不确定性估计。我们提出了一种产生预测集(几乎完全)的方法,可以在培训人群周围$ f $ divergence球中的任何测试分布提供正确的覆盖水平。该方法基于共形推断,仅在训练数据可交换的条件下,在有限样本中获得(几乎)有效的覆盖范围。我们方法的一个重要组成部分是估计预期的未来数据转移的数量并为其增强鲁棒性。我们开发估计器,并证明其在变化中的不确定性估计值的保护和有效性的一致性。通过在几个大规模基准数据集上进行实验,包括Recht等人的CIFAR-V4和Imagenet-V2数据集,我们提供了互补的经验结果,突出了可靠的预测有效性的重要性。
While the traditional viewpoint in machine learning and statistics assumes training and testing samples come from the same population, practice belies this fiction. One strategy -- coming from robust statistics and optimization -- is thus to build a model robust to distributional perturbations. In this paper, we take a different approach to describe procedures for robust predictive inference, where a model provides uncertainty estimates on its predictions rather than point predictions. We present a method that produces prediction sets (almost exactly) giving the right coverage level for any test distribution in an $f$-divergence ball around the training population. The method, based on conformal inference, achieves (nearly) valid coverage in finite samples, under only the condition that the training data be exchangeable. An essential component of our methodology is to estimate the amount of expected future data shift and build robustness to it; we develop estimators and prove their consistency for protection and validity of uncertainty estimates under shifts. By experimenting on several large-scale benchmark datasets, including Recht et al.'s CIFAR-v4 and ImageNet-V2 datasets, we provide complementary empirical results that highlight the importance of robust predictive validity.