# Traditional and Heavy-Tailed Self Regularization in Neural Network Models

arXiv: https://arxiv.org/abs/1901.08276 · HTML: https://mlsanity.com/paper/1901.08276/

## Key facts

- Cited by 105 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 24 Jan 2019.

## Built on by (most cited first, 30 of 105)

- [Intrinsic Dimension, Persistent Homology and Generalization in Neural Networks](https://mlsanity.com/paper/2111.13171/) (2021)
- [GradInit: Learning to Initialize Neural Networks for Stable and Efficient Training](https://mlsanity.com/paper/2102.08098/) (2021)
- [Heavy Tails in SGD and Compressibility of Overparametrized Neural Networks](https://mlsanity.com/paper/2106.03795/) (2021)
- [Towards Scalable and Versatile Weight Space Learning](https://mlsanity.com/paper/2406.09997/) (2024)
- [Model Zoos: A Dataset of Diverse Populations of Neural Network Models](https://mlsanity.com/paper/2209.14764/) (2022)
- [AlphaPruning: Using Heavy-Tailed Self Regularization Theory for Improved Layer-wise Pruning of Large Language Models](https://mlsanity.com/paper/2410.10912/) (2024)
- [Taxonomizing local versus global structure in neural network loss landscapes](https://mlsanity.com/paper/2107.11228/) (2021)
- [Spectral Evolution and Invariance in Linear-width Neural Networks](https://mlsanity.com/paper/2211.06506/) (2022)
- [Learning continuous models for continuous physics](https://mlsanity.com/paper/2202.08494/) (2022)
- [Generalization Bounds using Lower Tail Exponents in Stochastic Optimizers](https://mlsanity.com/paper/2108.00781/) (2021)
- [A Primer on Bayesian Neural Networks: Review and Debates](https://mlsanity.com/paper/2309.16314/) (2023)
- [Temperature Balancing, Layer-wise Weight Analysis, and Neural Network Training](https://mlsanity.com/paper/2312.00359/) (2023)
- [AlphaLoRA: Assigning LoRA Experts Based on Layer Training Quality](https://mlsanity.com/paper/2410.10054/) (2024)
- [Scaling Laws and Spectra of Shallow Neural Networks in the Feature Learning Regime](https://mlsanity.com/paper/2509.24882/) (2025)
- [Post-mortem on a deep learning contest: a Simpson's paradox and the complementary roles of scale metrics versus shape metrics](https://mlsanity.com/paper/2106.00734/) (2021)
- [Evaluating natural language processing models with generalization metrics that do not need access to any training or testing data](https://mlsanity.com/paper/2202.02842/) (2022)
- [Metric Space Magnitude and Generalisation in Neural Networks](https://mlsanity.com/paper/2305.05611/) (2023)
- [Deep neural networks with dependent weights: Gaussian Process mixture limit, heavy tails, sparsity and compressibility](https://mlsanity.com/paper/2205.08187/) (2022)
- [AlphaDecay: Module-wise Weight Decay for Heavy-Tailed Balancing in LLMs](https://mlsanity.com/paper/2506.14562/) (2025)
- [Algorithmic Stability of Heavy-Tailed Stochastic Gradient Descent on Least Squares](https://mlsanity.com/paper/2206.01274/) (2022)
- [Efficient Storage of Fine-Tuned Models via Low-Rank Approximation of Weight Residuals](https://mlsanity.com/paper/2305.18425/) (2023)
- [Monotonicity and Double Descent in Uncertainty Estimation with Gaussian Processes](https://mlsanity.com/paper/2210.07612/) (2022)
- [Unifying Low Dimensional Spectra in Deep Learning](https://mlsanity.com/paper/2404.06106/) (2024)
- [Edge of chaos as a guiding principle for modern neural network training](https://mlsanity.com/paper/2107.09437/) (2021)
- [Condense, Don't Just Prune: Enhancing Efficiency and Performance in MoE Layer Pruning](https://mlsanity.com/paper/2412.00069/) (2024)
- [Models of Heavy-Tailed Mechanistic Universality](https://mlsanity.com/paper/2506.03470/) (2025)
- [Eigenspectrum Analysis of Neural Networks without Aspect Ratio Bias](https://mlsanity.com/paper/2506.06280/) (2025)
- [Hyper-Representations: Self-Supervised Representation Learning on Neural Network Weights for Model Characteristic Prediction](https://mlsanity.com/paper/2110.15288/) (2021)
- [The Underlying Scaling Laws and Universal Statistical Structure of Complex Datasets](https://mlsanity.com/paper/2306.14975/) (2023)
- [Optimal scaling laws in learning hierarchical multi-index models](https://mlsanity.com/paper/2602.05846/) (2026)

## Abstract (arXiv)

Random Matrix Theory (RMT) is applied to analyze the weight matrices of Deep Neural Networks (DNNs), including both production quality, pre-trained models such as AlexNet and Inception, and smaller models trained from scratch, such as LeNet5 and a miniature-AlexNet. Empirical and theoretical results clearly indicate that the empirical spectral density (ESD) of DNN layer matrices displays signatures of traditionally-regularized statistical models, even in the absence of exogenously specifying traditional forms of regularization, such as Dropout or Weight Norm constraints. Building on recent results in RMT, most notably its extension to Universality classes of Heavy-Tailed matrices, we develop a theory to identify 5+1 Phases of Training, corresponding to increasing amounts of Implicit Self-Regularization. For smaller and/or older DNNs, this Implicit Self-Regularization is like traditional Tikhonov regularization, in that there is a `size scale' separating signal from noise. For state-of-the-art DNNs, however, we identify a novel form of Heavy-Tailed Self-Regularization, similar to the self-organization seen in the statistical physics of disordered systems. This implicit Self-Regularization can depend strongly on the many knobs of the training process. By exploiting the generalization gap phenomena, we demonstrate that we can cause a small model to exhibit all 5+1 phases of training simply by changing the batch size.
