This paper presents a method of zero-shot learning (ZSL) which poses ZSL as the missing data problem, rather than the missing label problem. While most popular methods in ZSL focus on learning the mapping function from the image feature space to the label embedding space, the proposed method explores a simple yet effective transductive framework in the reverse mapping. Our method estimates data distribution of unseen classes in the image feature space by transferring knowledge from the label embedding space. It assumes that data of each seen and unseen class follow Gaussian distribution in the image feature space and utilizes Gaussian mixture model to model data. The signature is introduced to describe the data distribution of each class. In experiments, our method obtains 87.38% and 61.08% mean accuracies on the Animals with Attributes (AwA) and the Caltech-UCSD Birds-200-2011 (CUB) datasets respectively, which outperforms the runner-up methods significantly by 4.95% and 6.38%. In addition, we also investigate the extension of our method to open-set classification.

本文探讨了零样本学习方法在解决'缺失数据问题'而非'缺失标签问题'时的有效性，通过将知识从标签嵌入空间转移到图像特征空间，估计未见过的类在图像特征空间的数据分布，实验表明，与现有方法相比，该方法在两个流行数据集上的表现更优

以缺失数据问题为形式的零样本学习