# Local Kernel Renormalization as a mechanism for feature learning in overparametrized Convolutional Neural Networks

arXiv: https://arxiv.org/abs/2307.11807 · HTML: https://mlsanity.com/paper/2307.11807/

## Key facts

- Cited by 19 papers in the map (data through 14 Oct 2026).
- Builds on 42 of its 77 references that are in the map.
- First posted on arXiv 21 Jul 2023.

## Builds on (most cited first, 30 of 42)

- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [Neural Tangent Kernel: Convergence and Generalization in Neural Networks](https://mlsanity.com/paper/1806.07572/) (2018)
- [Wide Neural Networks of Any Depth Evolve as Linear Models Under Gradient Descent](https://mlsanity.com/paper/1902.06720/) (2019)
- [On Lazy Training in Differentiable Programming](https://mlsanity.com/paper/1812.07956/) (2018)
- [Deep Neural Networks as Gaussian Processes](https://mlsanity.com/paper/1711.00165/) (2017)
- [On Exact Computation with an Infinitely Wide Neural Net](https://mlsanity.com/paper/1904.11955/) (2019)
- [A Mean Field View of the Landscape of Two-Layers Neural Networks](https://mlsanity.com/paper/1804.06561/) (2018)
- [On the Global Convergence of Gradient Descent for Over-parameterized Models using Optimal Transport](https://mlsanity.com/paper/1805.09545/) (2018)
- [The generalization error of random features regression: Precise asymptotics and double descent curve](https://mlsanity.com/paper/1908.05355/) (2019)
- [Gaussian Process Behaviour in Wide Deep Neural Networks](https://mlsanity.com/paper/1804.11271/) (2018)
- [Spectrum Dependent Learning Curves in Kernel Regression and Wide Neural Networks](https://mlsanity.com/paper/2002.02561/) (2020)
- [The Principles of Deep Learning Theory](https://mlsanity.com/paper/2106.10165/) (2021)
- [Bayesian Deep Convolutional Networks with Many Channels are Gaussian Processes](https://mlsanity.com/paper/1810.05148/) (2018)
- [Spectral Bias and Task-Model Alignment Explain Generalization in Kernel Regression and Infinitely Wide Neural Networks](https://mlsanity.com/paper/2006.13198/) (2020)
- [Finite Versus Infinite Neural Networks: an Empirical Study](https://mlsanity.com/paper/2007.15801/) (2020)
- [Deep Convolutional Networks as shallow Gaussian Processes](https://mlsanity.com/paper/1808.05587/) (2018)
- [Generalisation error in learning with random features and the hidden manifold model](https://mlsanity.com/paper/2002.09339/) (2020)
- [Learning curves of generic features maps for realistic datasets with a teacher-student model](https://mlsanity.com/paper/2102.08127/) (2021)
- [The Gaussian equivalence of generative models for learning with shallow neural networks](https://mlsanity.com/paper/2006.14709/) (2020)
- [Non-Gaussian processes and neural networks at finite widths](https://mlsanity.com/paper/1910.00019/) (2019)
- [Statistical Mechanics of Deep Linear Neural Networks: The Back-Propagating Kernel Renormalization](https://mlsanity.com/paper/2012.04030/) (2020)
- [Separation of Scales and a Thermodynamic Description of Feature Learning in Some CNNs](https://mlsanity.com/paper/2112.15383/) (2021)
- [Student-t Processes as Alternatives to Gaussian Processes](https://mlsanity.com/paper/1402.4306/) (2014)
- [Why bigger is not always better: on finite and infinite neural networks](https://mlsanity.com/paper/1910.08013/) (2019)
- [Bayes-optimal Learning of Deep Random Networks of Extensive-width](https://mlsanity.com/paper/2302.00375/) (2023)
- [Limitations of the NTK for Understanding Generalization in Deep Learning](https://mlsanity.com/paper/2206.10012/) (2022)
- [Deterministic equivalent and error universality of deep random features learning](https://mlsanity.com/paper/2302.00401/) (2023)
- [A self consistent theory of Gaussian Processes captures feature learning effects in finite CNNs](https://mlsanity.com/paper/2106.04110/) (2021)
- [Data-driven emergence of convolutional structure in neural networks](https://mlsanity.com/paper/2202.00565/) (2022)
- [Locality defeats the curse of dimensionality in convolutional teacher-student scenarios](https://mlsanity.com/paper/2106.08619/) (2021)

## Built on by (most cited first, 19 of 19)

- [Deep Linear Network Training Dynamics from Random Initialization: Data, Width, Depth, and Hyperparameter Transfer](https://mlsanity.com/paper/2502.02531/) (2025)
- [Adaptive kernel predictors from feature-learning infinite limits of neural networks](https://mlsanity.com/paper/2502.07998/) (2025)
- [Feature learning in finite-width Bayesian deep linear networks with multiple outputs and convolutional layers](https://mlsanity.com/paper/2406.03260/) (2024)
- [Bayesian RG Flow in Neural Network Field Theories](https://mlsanity.com/paper/2405.17538/) (2024)
- [Statistical mechanics of extensive-width Bayesian neural networks near interpolation](https://mlsanity.com/paper/2505.24849/) (2025)
- [Restoring balance: principled under/oversampling of data for optimal classification](https://mlsanity.com/paper/2405.09535/) (2024)
- [Bayesian Inference with Deep Weakly Nonlinear Networks](https://mlsanity.com/paper/2405.16630/) (2024)
- [Proportional infinite-width infinite-depth limit for deep linear neural networks](https://mlsanity.com/paper/2411.15267/) (2024)
- [Transfer Learning in Infinite Width Feature Learning Networks](https://mlsanity.com/paper/2507.04448/) (2025)
- [A unified theory of feature learning in RNNs and DNNs](https://mlsanity.com/paper/2602.15593/) (2026)
- [Optimal generalisation and learning transition in extensive-width shallow neural networks near interpolation](https://mlsanity.com/paper/2501.18530/) (2025)
- [Feature learning is decoupled from generalization in high capacity neural networks](https://mlsanity.com/paper/2507.19680/) (2025)
- [On Interpolation Formulas Describing Neural Network Generalization](https://mlsanity.com/paper/2603.13872/) (2026)
- [Kernel Renormalization in Bayesian Deep Neural Networks: the Equivalent Wishart Ansatz in the Proportional Regime](https://mlsanity.com/paper/2605.29684/) (2026)
- [Deep Neural Nets as Hamiltonians](https://mlsanity.com/paper/2503.23982/) (2025)
- [A simple mean field model of feature learning](https://mlsanity.com/paper/2510.15174/) (2025)
- [Statistical physics of deep learning: Optimal learning of a multi-layer perceptron near interpolation](https://mlsanity.com/paper/2510.24616/) (2025)
- [Large deviation principles for convolutional Bayesian neural networks](https://mlsanity.com/paper/2603.06023/) (2026)
- [A Function-Space Approach to the Statistical Mechanics of Learning Dynamics](https://mlsanity.com/paper/2609.09589/) (2026)

## Abstract (arXiv)

Feature learning, or the ability of deep neural networks to automatically learn relevant features from raw data, underlies their exceptional capability to solve complex tasks. However, feature learning seems to be realized in different ways in fully-connected (FC) or convolutional architectures (CNNs). Empirical evidence shows that FC neural networks in the infinite-width limit eventually outperform their finite-width counterparts. Since the kernel that describes infinite-width networks does not evolve during training, whatever form of feature learning occurs in deep FC architectures is not very helpful in improving generalization. On the other hand, state-of-the-art architectures with convolutional layers achieve optimal performances in the finite-width regime, suggesting that an effective form of feature learning emerges in this case. In this work, we present a simple theoretical framework that provides a rationale for these differences, in one hidden layer networks. First, we show that the generalization performance of a finite-width FC network can be obtained by an infinite-width network, with a suitable choice of the Gaussian priors. Second, we derive a finite-width effective action for an architecture with one convolutional hidden layer and compare it with the result available for FC networks. Remarkably, we identify a completely different form of kernel renormalization: whereas the kernel of the FC architecture is just globally renormalized by a single scalar parameter, the CNN kernel undergoes a local renormalization, meaning that the network can select the local components that will contribute to the final prediction in a data-dependent way. This finding highlights a simple mechanism for feature learning that can take place in overparametrized shallow CNNs, but not in shallow FC architectures or in locally connected neural networks without weight sharing.
