The Malignant Tail: Spectral Segregation of Label Noise in Over-Parameterized Networks
Researchers identify the 'Malignant Tail' phenomenon where over-parameterized neural networks segregate signal from noise during training, leading to harmful overfitting. They demonstrate that Stochastic Gradient Descent pushes label noise into high-frequency orthogonal subspaces while preserving semantic features in low-rank subspaces, and propose Explicit Spectral Truncation as a post-hoc solution to recover optimal generalization.