IEEE Trans Cybern. 2017 Mar;47(3):651-660. doi: 10.1109/TCYB.2016.2523538. Epub 2016 Feb 11.
In practical applications, the test data often have different distribution from the training data leading to suboptimal visual classification performance. Domain adaptation (DA) addresses this problem by designing classifiers that are robust to mismatched distributions. Existing DA algorithms use the unlabeled test data from target domain during training time in addition to the source domain data. However, target domain data may not always be available for training. We propose a blind DA algorithm that does not require target domain samples for training. For this purpose, we learn a global nonlinear extreme learning machine (ELM) model from the source domain data in an unsupervised fashion. The global ELM model is then used to initialize and learn class specific ELM models from the source domain data. During testing, the target domain features are augmented with the reconstructed features from the global ELM model. The resulting enriched features are then classified using the class specific ELM models based on minimum reconstruction error. Extensive experiments on 16 standard datasets show that despite blind learning, our method outperforms six existing state-of-the-art methods in cross domain visual recognition.
在实际应用中,测试数据的分布通常与训练数据不同,这导致视觉分类性能不佳。域自适应(DA)通过设计对不匹配分布具有鲁棒性的分类器来解决这个问题。现有的 DA 算法在训练过程中除了使用源域数据外,还使用目标域的未标记测试数据。然而,目标域数据并不总是可用于训练。我们提出了一种无需目标域样本进行训练的盲域自适应算法。为此,我们以无监督的方式从源域数据中学习全局非线性极端学习机(ELM)模型。然后,全局 ELM 模型用于从源域数据中初始化和学习特定于类的 ELM 模型。在测试时,用全局 ELM 模型重构的特征来扩充目标域特征。然后,基于最小重构误差,使用特定于类的 ELM 模型对得到的丰富特征进行分类。在 16 个标准数据集上的广泛实验表明,尽管是盲目学习,我们的方法在跨域视觉识别方面优于六种现有的最先进方法。