We present a novel method to combat domain shift when adapting classification models trained on one domain to other new domains with few or no target labels. In the existing literature, a prevailing solution paradigm is to learn domain-invariant feature representations so that a classifier learned on the source features generalizes well to the target features. However, such a classifier is inevitably biased to the source domain by overlooking the structure of the target data. Instead, we propose Self-Taught Labeling (SeTL), a new regularization approach that finds an auxiliary target-specific classifier for unlabeled data. During adaptation, this classifier is able to teach the target domain itself by providing \emph{unbiased accurate} pseudo labels. In particular, for each target data, we employ the memory bank to store the feature along with its soft label from the domain-shared classifier. Then we develop a non-parametric neighborhood aggregation strategy to generate new pseudo labels as well as confidence weights for unlabeled data. Though simply using the standard classification objective, SeTL significantly outperforms existing domain alignment techniques on a large variety of domain adaptation benchmarks. We expect that SeTL can provide a new perspective of addressing domain shift and inspire future research of domain adaptation and transfer learning.

该研究提出一种名为Auxiliary Target Domain-Oriented Classifier (ATDOC)的模型，旨在解决在无监督域适应中伪标签分布偏移和分类器偏置的问题。该模型基于最近邻居和内存机制，在多种领域适应基准和半监督任务上显着优于领域对齐技术和先前的半监督技术。

辅助目标领域分类器的域自适应