论文标题
针对无监督的域适应的部分共享的变异自动编码器与目标移动
Partially-Shared Variational Auto-encoders for Unsupervised Domain Adaptation with Target Shift
论文作者
论文摘要
本文提出了一种具有目标转移的无监督域适应(UDA)的新方法。目标移位是源和目标域之间标签分布不匹配的问题。通常,它是目标域中的类不平衡。实际上,这是UDA的重要问题。由于我们不知道目标域数据集中的标签,因此我们不知道其分布是否与源域数据集中的标签相同。许多传统方法通过最大程度地减少平均最大差异或对抗性训练来实现UDA的分配匹配;但是,这些方法隐含地假设分布的巧合,并且在目标变化的情况下不起作用。最近的一些UDA方法集中在阶级边界上,其中一些方法可用于靶向转移,但它们仅适用于分类而不适用于回归。 为了克服UDA中的目标移位问题,提出的方法(部分共享的变异自动编码器(PS-VAE))使用配对特征对齐方式而不是特征分布匹配。 PS-VAE通过基于自行车的架构的每个样本的转换域,同时保留其标签相关内容。为了评估PS-VAE的性能,我们进行了两个实验:UDA具有类不平衡的数字数据集(分类),而UDA从合成数据到人类置式估计中的真实观察(回归)。所提出的方法提出了其针对分类任务中阶级不平衡的鲁棒性,并以很大的边距优于回归任务中的其他方法。
This paper proposes a novel approach for unsupervised domain adaptation (UDA) with target shift. Target shift is a problem of mismatch in label distribution between source and target domains. Typically it appears as class-imbalance in target domain. In practice, this is an important problem in UDA; as we do not know labels in target domain datasets, we do not know whether or not its distribution is identical to that in the source domain dataset. Many traditional approaches achieve UDA with distribution matching by minimizing mean maximum discrepancy or adversarial training; however these approaches implicitly assume a coincidence in the distributions and do not work under situations with target shift. Some recent UDA approaches focus on class boundary and some of them are robust to target shift, but they are only applicable to classification and not to regression. To overcome the target shift problem in UDA, the proposed method, partially shared variational autoencoders (PS-VAEs), uses pair-wise feature alignment instead of feature distribution matching. PS-VAEs inter-convert domain of each sample by a CycleGAN-based architecture while preserving its label-related content. To evaluate the performance of PS-VAEs, we carried out two experiments: UDA with class-unbalanced digits datasets (classification), and UDA from synthesized data to real observation in human-pose-estimation (regression). The proposed method presented its robustness against the class-imbalance in the classification task, and outperformed the other methods in the regression task with a large margin.