Two-Dimensional Multilabel Active Learning with an Efficient Online Adaptation Model for Image Classification
Issue No. 10 - October (2009 vol. 31)
Guo-Jun Qi , University of Illinois at Urbana-Champaign, Urbana
Xian-Sheng Hua , Microsoft Research Asia, Beijing
Yong Rui , Microsoft China R&D Group, Beijing
Jinhui Tang , National University of Singapore, Singapore
Hong-Jiang Zhang , Microsoft Advanced Technology Center, Beijing
Conventional active learning dynamically constructs the training set only along the sample dimension. While this is the right strategy in binary classification, it is suboptimal for multilabel image classification. We argue that for each selected sample, only some effective labels need to be annotated while others can be inferred by exploring the label correlations. The reason is that the contributions of different labels to minimizing the classification error are different due to the inherent label correlations. To this end, we propose to select sample-label pairs, rather than only samples, to minimize a multilabel Bayesian classification error bound. We call it two-dimensional active learning because it considers both the sample dimension and the label dimension. Furthermore, as the number of training samples increases rapidly over time due to active learning, it becomes intractable for the offline learner to retrain a new model on the whole training set. So we develop an efficient online learner to adapt the existing model with the new one by minimizing their model distance under a set of multilabel constraints. The effectiveness and efficiency of the proposed method are evaluated on two benchmark data sets and a realistic image collection from a real-world image sharing Web site—Corbis.
Active learning, online adaption, multilabel classification, image annotation.
H. Zhang, Y. Rui, G. Qi, J. Tang and X. Hua, "Two-Dimensional Multilabel Active Learning with an Efficient Online Adaptation Model for Image Classification," in IEEE Transactions on Pattern Analysis & Machine Intelligence, vol. 31, no. , pp. 1880-1897, 2008.