From two unlabeled (U) datasets with different class priors, we can train a binary classifier by empirical risk minimization, which is called UU classification. It is promising since UU methods are compatible with any neural network (NN) architecture and optimizer as if it is standard supervised classification. In this paper, however, we find that UU methods may suffer severe overfitting, and there is a high co-occurrence between the overfitting and the negative empirical risk regardless of datasets, NN architectures, and optimizers. Hence, to mitigate the overfitting problem of UU methods, we propose to keep two parts of the empirical risk (i.e., false positive and false negative) non-negative by wrapping them in a family of correction functions. We theoretically show that the corrected risk estimator is still asymptotically unbiased and consistent; furthermore we establish an estimation error bound for the corrected risk minimizer. Experiments with feedforward/residual NNs on standard benchmarks demonstrate that our proposed correction can successfully mitigate the overfitting of UU methods and significantly improve the classification accuracy.

本文介绍一个基于经验风险最小化的无标注二分类方法。该方法有时可能会出现严重的过拟合。因此，我们提出了一种校正函数来限制过拟合，并证明了校正后的风险估计器的一致性和估计误差界限。实验结果显示，我们的方法成功地缓解了 UU 方法的过拟合问题，并显著提高了分类准确性。

从两个未标记数据集进行监督分类中缓解过拟合：一种一致的风险校正方法