Visual Domain Adaptation Exploiting ConfidenceSamples Domain adaptation methods are used to address a problem, in which train scenario (source domain) and test scenario (target domain) are different. The existing methods mainly perform adaptation via reducing domain discrepancy from the view of a probability distribution. However, the idea of probability distribution matching always leads to a complex optimization process. Thereby these methods are difficult to apply in some scenario like online application or fast perception in dynamic environments. In this paper, we propose a new and simple domain adaptation method that utilizes confidence samples to facilitate the classifier training on the target domain. Here, the confidencesamples are a subset of the target samples, and they have very credibly predicted labels. In order to detect the samples, a Category Similarity Collaborative Representation (CSCR) is first developed, by which the raw labels of all target samples are predicted using the smallest projection error according to the law of category. After this, the confidence score of the raw predicted labels is evaluated by the energy context information of CSCR. Finally, the target samples with a high confidence score are selected. Because of the linearity of CSCR, our method avoids complex optimization for matching the probability distribution. Empirical studies on a standard dataset demonstrate the advantages of our method.

CUDA: Contradistinguisher for Unsupervised Domain Adaptation Humans are very sophisticated in learning new information on a completely unknown domain because humans can contradistinguish, i.e., distinguish by contrasting qualities. We learn on a new unknown domain by jointly using unsupervised information directly from unknown domain and supervised information previously acquired knowledge from some other domain. Motivated by this supervisedunsupervised joint learning, we propose a simple model referred as Contradistinguisher (CTDR) for unsupervised domain adaptation whose objective is to jointly learn to contradistinguish on unlabeled target domain in a fully unsupervised manner along with prior knowledge acquired by supervised learning on an entirely different domain. Most recent works in domain adaptation rely on an indirect way of first aligning the source and target domain distributions and then learn a classifier on labeled source domain to classify target domain. This approach of indirect way of addressing the real task of unlabeled target domain classification has three main drawbacks. (i) The subtask of obtaining a perfect alignment of the domain in itself might be impossible due to large domain shift (e.g., language domains). (ii) The use of multiple classifiers to align the distributions, unnecessarily increases the complexity of the neural networks leading to overfitting in many cases. (iii) Due to distribution alignment, the domain specific information is lost as the domains get morphed. In this work, we propose a simple and direct approach that does not require domain alignment. We jointly learn CTDR on both source and target distribution for unsupervised domain adaptation task using contradistinguish loss for the unlabeled target domain in conjunction with supervised loss for labeled source domain. Our experiments show that avoiding domain alignment by directly addressing the task of unlabeled target domain classification using CTDR achieves stateoftheart results on eight visual and four language benchmark domain adaptation datasets.