Robust estimation is an important problem in statistics which aims at providing a reasonable estimator when the data-generating distribution lies within an appropriately defined ball around an uncontaminated distribution. Although minimax rates of estimation have been established in recent years, many existing robust estimators with provably optimal convergence rates are also computationally intractable. In this paper, we study several estimation problems under a Wasserstein contamination model and present computationally tractable estimators motivated by generative adversarial networks (GANs). Specifically, we analyze properties of Wasserstein GAN-based estimators for location estimation, covariance matrix estimation, and linear regression and show that our proposed estimators are minimax optimal in many scenarios. Finally, we present numerical results which demonstrate the effectiveness of our estimators.
翻译:强有力的估算是统计中的一个重要问题,统计的目的是在数据生成分布处于一个定义合理的球中时提供一个合理的估算器。尽管近年来已经确定了最低估计率,但许多现有的稳健估算器在计算上也是棘手的。在本文中,我们研究了瓦塞斯坦污染模型下的若干估算问题,并提出了由基因对抗网络(GANs)驱动的可计算可移动估算器。具体地说,我们分析了瓦塞尔斯坦GAN的估算器在地点估计、变量矩阵估计和线性回归方面的特性,并表明我们提议的估算器在许多情景中都是最理想的。最后,我们提出了数字结果,显示了我们的估算器的有效性。