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EasyEnsemble.M for Multiclass Imbalance Problem |
LI Qian-Qian1, LIU Xu-Ying1,2 |
1.Key Laboratory of Computer Network and Information Integration, Ministry of Education, School of Computer Science and Engineering, Southeast University, Nanjing 211189 2.National Key Laboratory for Novel Software Technology, Nanjing University, Nanjing 211189 |
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Abstract The potential useful information in the majority class is ignored by stochastic under-sampling. When under-sampling is applied to multi-class imbalance problem, this situation becomes even worse. In this paper, EasyEnsemble.M for multi-class imbalance problem is proposed. The potential useful information contained in the majority classes which is ignored is explored by stochastic sampling the majority classes for multiple times. Then, sub-classifiers are learned and a strong classifier is obtained by using hybrid ensemble techniques. Experimental results show that EasyEnsemble.M is superior to other frequently used multi-class imbalance learning methods when G-mean is used as performance measure.
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Received: 13 May 2013
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