Learning with Noisy Labels by Adaptive Gradient-Based Outlier Removal
Anastasiia Sedova, Lena Zellinger, Benjamin Roth
TL;DR
AGRA addresses label noise by replacing pre-cleaning with adaptive, gradient-based outlier removal during training. It computes per-sample gradients $\\nabla\\widetilde{L}(x_t,y_t)$ and a batch comparison gradient $\\nabla\\widetilde{L}_{com}$, using their cosine similarity $sim_{y_t}$ to decide whether to keep, remove, or relabel samples via flexible rules such as $sim_{y_t} \le 0$ or $sim_{y'} > sim_{y_t}$. The method is compatible with standard losses and a differentiable $F_1$ loss, and it employs class-aware sampling for the comparison batch to handle imbalance. Across seven data-rich experiments spanning NLP and vision, AGRA outperforms several baselines, sometimes matching a model trained on gold labels, and ablations show the benefit of $F_1$-based losses and weighted sampling in noisy settings. This work demonstrates that dynamic, gradient-guided data usage during training can yield robust performance on noisy data without assuming a particular noise distribution, with practical implications for weak supervision and large-scale labeling regimes.
Abstract
An accurate and substantial dataset is essential for training a reliable and well-performing model. However, even manually annotated datasets contain label errors, not to mention automatically labeled ones. Previous methods for label denoising have primarily focused on detecting outliers and their permanent removal - a process that is likely to over- or underfilter the dataset. In this work, we propose AGRA: a new method for learning with noisy labels by using Adaptive GRAdient-based outlier removal. Instead of cleaning the dataset prior to model training, the dataset is dynamically adjusted during the training process. By comparing the aggregated gradient of a batch of samples and an individual example gradient, our method dynamically decides whether a corresponding example is helpful for the model at this point or is counter-productive and should be left out for the current update. Extensive evaluation on several datasets demonstrates AGRA's effectiveness, while a comprehensive results analysis supports our initial hypothesis: permanent hard outlier removal is not always what model benefits the most from.
