# Neural Tangent Kernel Beyond the Infinite-Width Limit: Effects of Depth and Initialization

arXiv: https://arxiv.org/abs/2202.00553 · HTML: https://mlsanity.com/paper/2202.00553/

## Key facts

- Cited by 30 papers in the map (data through 14 Oct 2026).
- Builds on 30 of its 39 references that are in the map.
- First posted on arXiv 1 Feb 2022.

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

- [Neural Tangent Kernel: Convergence and Generalization in Neural Networks](https://mlsanity.com/paper/1806.07572/) (2018)
- [Deep Learning and the Information Bottleneck Principle](https://mlsanity.com/paper/1503.02406/) (2015)
- [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)
- [When and why PINNs fail to train: A neural tangent kernel perspective](https://mlsanity.com/paper/2007.14527/) (2020)
- [On Exact Computation with an Infinitely Wide Neural Net](https://mlsanity.com/paper/1904.11955/) (2019)
- [Gaussian Process Behaviour in Wide Deep Neural Networks](https://mlsanity.com/paper/1804.11271/) (2018)
- [Exponential expressivity in deep neural networks through transient chaos](https://mlsanity.com/paper/1606.05340/) (2016)
- [Deep Information Propagation](https://mlsanity.com/paper/1611.01232/) (2016)
- [Deep learning versus kernel learning: an empirical study of loss landscape geometry and the time evolution of the Neural Tangent Kernel](https://mlsanity.com/paper/2010.15110/) (2020)
- [Graph Neural Tangent Kernel: Fusing Graph Neural Networks with Graph Kernels](https://mlsanity.com/paper/1905.13192/) (2019)
- [Finite Versus Infinite Neural Networks: an Empirical Study](https://mlsanity.com/paper/2007.15801/) (2020)
- [Scaling Limits of Wide Neural Networks with Weight Sharing: Gaussian Process Behavior, Gradient Independence, and Neural Tangent Kernel Derivation](https://mlsanity.com/paper/1902.04760/) (2019)
- [Tensor Programs II: Neural Tangent Kernel for Any Architecture](https://mlsanity.com/paper/2006.14548/) (2020)
- [Finite Depth and Width Corrections to the Neural Tangent Kernel](https://mlsanity.com/paper/1909.05989/) (2019)
- [The Neural Tangent Kernel in High Dimensions: Triple Descent and a Multi-Scale Theory of Generalization](https://mlsanity.com/paper/2008.06786/) (2020)
- [Dynamics of Deep Neural Networks and Neural Tangent Hierarchy](https://mlsanity.com/paper/1909.08156/) (2019)
- [Universal Statistics of Fisher Information in Deep Neural Networks: Mean Field Approach](https://mlsanity.com/paper/1806.01316/) (2018)
- [Harnessing the Power of Infinitely Wide Deep Nets on Small-data Tasks](https://mlsanity.com/paper/1910.01663/) (2019)
- [Mean Field Residual Networks: On the Edge of Chaos](https://mlsanity.com/paper/1712.08969/) (2017)
- [Scaling description of generalization with number of parameters in deep learning](https://mlsanity.com/paper/1901.01608/) (2019)
- [The Recurrent Neural Tangent Kernel](https://mlsanity.com/paper/2006.10246/) (2020)
- [Why Do Deep Residual Networks Generalize Better than Deep Feedforward Networks? -- A Neural Tangent Kernel Perspective](https://mlsanity.com/paper/2002.06262/) (2020)
- [Why bigger is not always better: on finite and infinite neural networks](https://mlsanity.com/paper/1910.08013/) (2019)
- [Deep Networks and the Multiple Manifold Problem](https://mlsanity.com/paper/2008.11245/) (2020)
- [Analyzing Finite Neural Networks: Can We Trust Neural Tangent Kernel Theory?](https://mlsanity.com/paper/2012.04477/) (2020)
- [The Future is Log-Gaussian: ResNets and Their Infinite-Depth-and-Width Limit at Initialization](https://mlsanity.com/paper/2106.04013/) (2021)
- [Kernel-Based Smoothness Analysis of Residual Networks](https://mlsanity.com/paper/2009.10008/) (2020)
- [Label-Aware Neural Tangent Kernel: Toward Better Generalization and Local Elasticity](https://mlsanity.com/paper/2010.11775/) (2020)
- [Taylorized Training: Towards Better Approximation of Neural Network Training at Finite Width](https://mlsanity.com/paper/2002.04010/) (2020)

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

- [Diverse Weight Averaging for Out-of-Distribution Generalization](https://mlsanity.com/paper/2205.09739/) (2022)
- [Mind the spikes: Benign overfitting of kernels and neural networks in fixed dimension](https://mlsanity.com/paper/2305.14077/) (2023)
- [The Challenges of the Nonlinear Regime for Physics-Informed Neural Networks](https://mlsanity.com/paper/2402.03864/) (2024)
- [Neural (Tangent Kernel) Collapse](https://mlsanity.com/paper/2305.16427/) (2023)
- [How connectivity structure shapes rich and lazy learning in neural circuits](https://mlsanity.com/paper/2310.08513/) (2023)
- [Neural Tangent Kernel Analysis to Probe Convergence in Physics-informed Neural Solvers: PIKANs vs. PINNs](https://mlsanity.com/paper/2506.07958/) (2025)
- [Approximation results for Gradient Descent trained Shallow Neural Networks in 1d](https://mlsanity.com/paper/2209.08399/) (2022)
- [Efficient Parametric Approximations of Neural Network Function Space Distance](https://mlsanity.com/paper/2302.03519/) (2023)
- [Semantic Tube Prediction: Beating LLM Data Efficiency with JEPA](https://mlsanity.com/paper/2602.22617/) (2026)
- [KHRONOS: a Kernel-Based Neural Architecture for Rapid, Resource-Efficient Scientific Computation](https://mlsanity.com/paper/2505.13315/) (2025)
- [Engineering flexible machine learning systems by traversing functionally-invariant paths](https://mlsanity.com/paper/2205.00334/) (2022)
- [Homotopy Relaxation Training Algorithms for Infinite-Width Two-Layer ReLU Neural Networks](https://mlsanity.com/paper/2309.15244/) (2023)
- [Finite-Width Neural Tangent Kernels from Feynman Diagrams](https://mlsanity.com/paper/2508.11522/) (2025)
- [Approximation Results for Gradient Descent trained Neural Networks](https://mlsanity.com/paper/2309.04860/) (2023)
- [GradPCA: Leveraging NTK Alignment for Reliable Out-of-Distribution Detection](https://mlsanity.com/paper/2505.16017/) (2025)
- [Revisiting Glorot Initialization for Long-Range Linear Recurrences](https://mlsanity.com/paper/2505.19827/) (2025)
- [Unifying Learning Dynamics and Generalization in Transformers Scaling Law](https://mlsanity.com/paper/2512.22088/) (2025)
- [An Adaptive Tangent Feature Perspective of Neural Networks](https://mlsanity.com/paper/2308.15478/) (2023)
- [Depth-induced NTK: Bridging Over-parameterized Neural Networks and Deep Neural Kernels](https://mlsanity.com/paper/2511.05585/) (2025)
- [A new initialisation to Control Gradients in Sinusoidal Neural network](https://mlsanity.com/paper/2512.06427/) (2025)
- [The kernel-balanced equation for deep neural networks](https://mlsanity.com/paper/2309.07367/) (2023)
- [Infinite Width Graph Neural Networks for Node Regression/ Classification](https://mlsanity.com/paper/2310.08176/) (2023)
- [A simple theory for training response of deep neural networks](https://mlsanity.com/paper/2405.04074/) (2024)
- [Scalable Data Attribution via Forward-Only Test-Time Inference](https://mlsanity.com/paper/2511.19803/) (2025)
- [Loop Corrections in Random Feature Models: Training Error and Generalization Gap](https://mlsanity.com/paper/2604.12827/) (2026)
- [Man, Machine, and Mathematics](https://mlsanity.com/paper/2604.27052/) (2026)
- [When Prompts Interact: Assessing Prompt Arithmetic for Deconfounding under Distribution Shift](https://mlsanity.com/paper/2605.03096/) (2026)
- [How Long Does Infinite Width Last? Signal Propagation in Long-Range Linear Recurrences](https://mlsanity.com/paper/2605.05113/) (2026)
- [Geometric Dyson Brownian Motions and the Free Log-Normal Limit for a Non-Square Gaussian Matrix Product](https://mlsanity.com/paper/2606.30831/) (2026)
- [Kernel Reboot: Breaking the Boundaries of Neural Tangent Kernels for Neural Fields](https://mlsanity.com/paper/2609.03117/) (2026)

## Abstract (arXiv)

Neural Tangent Kernel (NTK) is widely used to analyze overparametrized neural networks due to the famous result by Jacot et al. (2018): in the infinite-width limit, the NTK is deterministic and constant during training. However, this result cannot explain the behavior of deep networks, since it generally does not hold if depth and width tend to infinity simultaneously. In this paper, we study the NTK of fully-connected ReLU networks with depth comparable to width. We prove that the NTK properties depend significantly on the depth-to-width ratio and the distribution of parameters at initialization. In fact, our results indicate the importance of the three phases in the hyperparameter space identified in Poole et al. (2016): ordered, chaotic and the edge of chaos (EOC). We derive exact expressions for the NTK dispersion in the infinite-depth-and-width limit in all three phases and conclude that the NTK variability grows exponentially with depth at the EOC and in the chaotic phase but not in the ordered phase. We also show that the NTK of deep networks may stay constant during training only in the ordered phase and discuss how the structure of the NTK matrix changes during training.
