“…Recent examples are multi-label learning based on SVM (Chang et al, 2017 ), based on deep learning (Mai et al, 2018 ), and based on ensemble classification (Büyükçakir et al, 2018 ). For very large classification space, extreme multi-label classification is proposed, e.g., a method based on graph embedding (Tagami, 2017 ), a method based on convolutional neural network (CNN) (Liu et al, 2017 ), and a method based on attention model of neural networks (Wang et al, 2018 ). Moreover, label hierarchy also can be considered so that part-of, is-a, and inclusion relationships are extracted from external data sources such as Wikipedia in the classification task (Bairi et al, 2016 ; Xie et al, 2017 ).…”