# A Mean-field Analysis of Deep ResNet and Beyond: Towards Provable Optimization Via Overparameterization From Depth

arXiv: https://arxiv.org/abs/2003.05508 · HTML: https://mlsanity.com/paper/2003.05508/

## Key facts

- Cited by 56 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 11 Mar 2020.

## Built on by (most cited first, 30 of 56)

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- [Over-Parameterization Exponentially Slows Down Gradient Descent for Learning a Single Neuron](https://mlsanity.com/paper/2302.10034/) (2023)
- [Overparameterization of deep ResNet: zero loss and mean-field analysis](https://mlsanity.com/paper/2105.14417/) (2021)
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- [ResIST: Layer-Wise Decomposition of ResNets for Distributed Training](https://mlsanity.com/paper/2107.00961/) (2021)
- [How Over-Parameterization Slows Down Gradient Descent in Matrix Sensing: The Curses of Symmetry and Initialization](https://mlsanity.com/paper/2310.01769/) (2023)
- [The Hidden Width of Deep ResNets: Tight Error Bounds and Phase Diagram](https://mlsanity.com/paper/2509.10167/) (2025)
- [Global Convergence of Three-layer Neural Networks in the Mean Field Regime](https://mlsanity.com/paper/2105.05228/) (2021)
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- [One-Layer Transformer Provably Learns One-Nearest Neighbor In Context](https://mlsanity.com/paper/2411.10830/) (2024)
- [Analysis of feature learning in weight-tied autoencoders via the mean field lens](https://mlsanity.com/paper/2102.08373/) (2021)
- [Why Lottery Ticket Wins? A Theoretical Perspective of Sample Complexity on Pruned Neural Networks](https://mlsanity.com/paper/2110.05667/) (2021)
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- [Solving PDEs on Unknown Manifolds with Machine Learning](https://mlsanity.com/paper/2106.06682/) (2021)
- [On the Global Convergence of Gradient Descent for multi-layer ResNets in the mean-field regime](https://mlsanity.com/paper/2110.02926/) (2021)
- [On the Convergence of Shallow Neural Network Training with Randomly Masked Neurons](https://mlsanity.com/paper/2112.02668/) (2021)
- [Stationary Density Estimation of Ito Diffusions Using Deep Learning](https://mlsanity.com/paper/2109.03992/) (2021)
- [Provably convergent quasistatic dynamics for mean-field two-player zero-sum games](https://mlsanity.com/paper/2202.10947/) (2022)
- [Depth Separation with Multilayer Mean-Field Networks](https://mlsanity.com/paper/2304.01063/) (2023)
- [Inverse Depth Scaling From Most Layers Being Similar](https://mlsanity.com/paper/2602.05970/) (2026)
- [Understanding the training of infinitely deep and wide ResNets with Conditional Optimal Transport](https://mlsanity.com/paper/2403.12887/) (2024)
- [Wasserstein Flow Meets Replicator Dynamics: A Mean-Field Analysis of Representation Learning in Actor-Critic](https://mlsanity.com/paper/2112.13530/) (2021)
- [On skip connections and normalisation layers in deep optimisation](https://mlsanity.com/paper/2210.05371/) (2022)

## Abstract (arXiv)

Training deep neural networks with stochastic gradient descent (SGD) can often achieve zero training loss on real-world tasks although the optimization landscape is known to be highly non-convex. To understand the success of SGD for training deep neural networks, this work presents a mean-field analysis of deep residual networks, based on a line of works that interpret the continuum limit of the deep residual network as an ordinary differential equation when the network capacity tends to infinity. Specifically, we propose a new continuum limit of deep residual networks, which enjoys a good landscape in the sense that every local minimizer is global. This characterization enables us to derive the first global convergence result for multilayer neural networks in the mean-field regime. Furthermore, without assuming the convexity of the loss landscape, our proof relies on a zero-loss assumption at the global minimizer that can be achieved when the model shares a universal approximation property. Key to our result is the observation that a deep residual network resembles a shallow network ensemble, i.e. a two-layer network. We bound the difference between the shallow network and our ResNet model via the adjoint sensitivity method, which enables us to apply existing mean-field analyses of two-layer networks to deep networks. Furthermore, we propose several novel training schemes based on the new continuous model, including one training procedure that switches the order of the residual blocks and results in strong empirical performance on the benchmark datasets.
