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arXiv · 2401.02591

Synthetic Information towards Maximum Posterior Ratio for deep learning on Imbalanced Data

Hung Nguyen·Morris Chang
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Abstract

This study examines the impact of class-imbalanced data on deep learning models and proposes a technique for data balancing by generating synthetic data for the minority class. Unlike random-based oversampling, our method prioritizes balancing the informative regions by identifying high entropy samples. Generating well-placed synthetic data can enhance machine learning algorithms accuracy and efficiency, whereas poorly-placed ones may lead to higher misclassification rates. We introduce an algorithm that maximizes the probability of generating a synthetic sample in the correct region of its class by optimizing the class posterior ratio. Additionally, to maintain data topology, synthetic data are generated within each minority sample's neighborhood. Our experimental results on forty-one datasets demonstrate the superior performance of our technique in enhancing deep-learning models.

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Hung Nguyen, Morris Chang. 2024-01-05. Synthetic Information towards Maximum Posterior Ratio for deep learning on Imbalanced Data. https://doi.org/10.1109/tai.2023.3330949

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