Timezone: »

 
Poster
MESA: Boost Ensemble Imbalanced Learning with MEta-SAmpler
Zhining Liu · Pengfei Wei · Jing Jiang · Wei Cao · Jiang Bian · Yi Chang

Wed Dec 09 09:00 AM -- 11:00 AM (PST) @ Poster Session 3 #762
in Poster Session 4 »

Imbalanced learning (IL), i.e., learning unbiased models from class-imbalanced data, is a challenging problem. Typical IL methods including resampling and reweighting were designed based on some heuristic assumptions. They often suffer from unstable performance, poor applicability, and high computational cost in complex tasks where their assumptions do not hold. In this paper, we introduce a novel ensemble IL framework named MESA. It adaptively resamples the training set in iterations to get multiple classifiers and forms a cascade ensemble model. MESA directly learns the sampling strategy from data to optimize the final metric beyond following random heuristics. Moreover, unlike prevailing meta-learning-based IL solutions, we decouple the model-training and meta-training in MESA by independently train the meta-sampler over task-agnostic meta-data. This makes MESA generally applicable to most of the existing learning models and the meta-sampler can be efficiently applied to new tasks. Extensive experiments on both synthetic and real-world tasks demonstrate the effectiveness, robustness, and transferability of MESA. Our code is available at https://github.com/ZhiningLiu1998/mesa.

Author Information

Zhining Liu (Jilin University)
Pengfei Wei (National University of Singapore)
Jing Jiang (University of Technology Sydney)
Wei Cao (MSRA)
Jiang Bian (Microsoft)
Yi Chang (Jilin University)

More from the Same Authors