Understanding Blooming Human Groups in Social Networks

Human group, which indicates the people who share similar characteristics, is used to categorize humans into distinct populations or groups. In recent years, with the explosive growth of image, new concepts of human group are blooming in social networks . People in the same human group can be categorized by their facial and clothes appearance characteristics. In this work, we propose an approach to understanding the new concepts of human group with few positive samples. To this end, we construct visual models crossing two modalities related to human images and surrounding texts. Two convolutional neural networks based on face and upper body are constructed separately. Two different convolutional neural networks (CNNs) architectures are explored for visual pre-traing. To assist the human group recognition, we also merge global convolutional feature of the image. The surrounding texts are represented by semantical vectors and utilized as image labels. We transform words in the text into fixed length vectors by the skip-gram model. Then the texts corresponding to each image are converted into one feature vector by sparse coding and max pooling. Given a few positive samples of new concepts of human group, the visual model can be improved to understand the semantical meaning of the new label. The experimental results demonstrate the effectiveness of the proposed visual model and show the excellent learning capacity with few samples.