Affiliations: [a] State Key Laboratory for Novel Software Technology at Nanjing University, Nanjing University, Nanjing, Jiangsu, China | [b] Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
Correspondence:
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Corresponding author: Mingcai Chen, State Key Laboratory for Novel Software Technology at Nanjing University, Nanjing University, Nanjing, Jiangsu, China. E-mail: chenmc@smail.nju.edu.cn.
Abstract: Real-world machine learning applications seldom provide perfect labeled data, posing a challenge in developing models robust to noisy labels. Recent methods prioritize noise filtering based on the discrepancies between model predictions and the provided noisy labels, assuming samples with minimal classification losses to be clean. In this work, we capitalize on the consistency between the learned model and the complete noisy dataset, employing the data’s rich representational and topological information. We introduce LaplaceConfidence, a method that to obtain label confidence (i.e., clean probabilities) utilizing the Laplacian energy. Specifically, it first constructs graphs based on the feature representations of all noisy samples and minimizes the Laplacian energy to produce a low-energy graph. Clean labels should fit well into the low-energy graph while noisy ones should not, allowing our method to determine data’s clean probabilities. Furthermore, LaplaceConfidence is embedded into a holistic method for robust training, where co-training technique generates unbiased label confidence and label refurbishment technique better utilizes it. We also explore the dimensionality reduction technique to accommodate our method on large-scale noisy datasets. Our experiments demonstrate that LaplaceConfidence outperforms state-of-the-art methods on benchmark datasets under both synthetic and real-world noise. Code available at https://github.com/chenmc1996/LaplaceConfidence.
Keywords: Learning with noisy labels, graph energy, label refurbishment
