# The Implicit Bias for Adaptive Optimization Algorithms on Homogeneous Neural Networks

arXiv: https://arxiv.org/abs/2012.06244 · HTML: https://mlsanity.com/paper/2012.06244/

## Key facts

- Cited by 46 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 11 Dec 2020.

## Built on by (most cited first, 30 of 46)

- [Explaining grokking through circuit efficiency](https://mlsanity.com/paper/2309.02390/) (2023)
- [Adaptive Gradient Methods at the Edge of Stability](https://mlsanity.com/paper/2207.14484/) (2022)
- [The Slingshot Mechanism: An Empirical Study of Adaptive Optimizers and the Grokking Phenomenon](https://mlsanity.com/paper/2206.04817/) (2022)
- [Dichotomy of Early and Late Phase Implicit Biases Can Provably Induce Grokking](https://mlsanity.com/paper/2311.18817/) (2023)
- [Transformers as Support Vector Machines](https://mlsanity.com/paper/2308.16898/) (2023)
- [Max-Margin Token Selection in Attention Mechanism](https://mlsanity.com/paper/2306.13596/) (2023)
- [Implicit Bias of AdamW: ℓ_∞ Norm Constrained Optimization](https://mlsanity.com/paper/2404.04454/) (2024)
- [Implicit Bias of Spectral Descent and Muon on Multiclass Separable Data](https://mlsanity.com/paper/2502.04664/) (2025)
- [Implicit Bias of Gradient Descent on Reparametrized Models: On Equivalence to Mirror Descent](https://mlsanity.com/paper/2207.04036/) (2022)
- [Topology-aware Generalization of Decentralized SGD](https://mlsanity.com/paper/2206.12680/) (2022)
- [The Implicit Bias of Adam on Separable Data](https://mlsanity.com/paper/2406.10650/) (2024)
- [Mechanics of Next Token Prediction with Self-Attention](https://mlsanity.com/paper/2403.08081/) (2024)
- [Don't blame Dataset Shift! Shortcut Learning due to Gradients and Cross Entropy](https://mlsanity.com/paper/2308.12553/) (2023)
- [A Fast Optimization View: Reformulating Single Layer Attention in LLM Based on Tensor and SVM Trick, and Solving It in Matrix Multiplication Time](https://mlsanity.com/paper/2309.07418/) (2023)
- [On the Implicit Bias of Adam](https://mlsanity.com/paper/2309.00079/) (2023)
- [Mirror Descent Maximizes Generalized Margin and Can Be Implemented Efficiently](https://mlsanity.com/paper/2205.12808/) (2022)
- [Two Sides of One Coin: the Limits of Untuned SGD and the Power of Adaptive Methods](https://mlsanity.com/paper/2305.12475/) (2023)
- [Emergent Misalignment is Easy, Narrow Misalignment is Hard](https://mlsanity.com/paper/2602.07852/) (2026)
- [Does Momentum Change the Implicit Regularization on Separable Data?](https://mlsanity.com/paper/2110.03891/) (2021)
- [Flavors of Margin: Implicit Bias of Steepest Descent in Homogeneous Neural Networks](https://mlsanity.com/paper/2410.22069/) (2024)
- [A Unified Approach to Controlling Implicit Regularization via Mirror Descent](https://mlsanity.com/paper/2306.13853/) (2023)
- [The Rich and the Simple: On the Implicit Bias of Adam and SGD](https://mlsanity.com/paper/2505.24022/) (2025)
- [The Implicit Bias of Adam and Muon on Smooth Homogeneous Neural Networks](https://mlsanity.com/paper/2602.16340/) (2026)
- [Understanding the robustness difference between stochastic gradient descent and adaptive gradient methods](https://mlsanity.com/paper/2308.06703/) (2023)
- [Learning to Compress: Local Rank and Information Compression in Deep Neural Networks](https://mlsanity.com/paper/2410.07687/) (2024)
- [Continuous-Time Analysis of Adaptive Optimization and Normalization](https://mlsanity.com/paper/2411.05746/) (2024)
- [The Effect of Mini-Batch Noise on the Implicit Bias of Adam](https://mlsanity.com/paper/2602.01642/) (2026)
- [A Mirror Descent Perspective of Smoothed Sign Descent](https://mlsanity.com/paper/2410.14158/) (2024)
- [OLion: Approaching the Hadamard Ideal by Intersecting Spectral and ℓ∞ Implicit Biases](https://mlsanity.com/paper/2602.01105/) (2026)
- [Muon Learns More Robust and Transferable Features than Adam](https://mlsanity.com/paper/2606.09658/) (2026)

## Abstract (arXiv)

Despite their overwhelming capacity to overfit, deep neural networks trained by specific optimization algorithms tend to generalize well to unseen data. Recently, researchers explained it by investigating the implicit regularization effect of optimization algorithms. A remarkable progress is the work (Lyu&Li, 2019), which proves gradient descent (GD) maximizes the margin of homogeneous deep neural networks. Except GD, adaptive algorithms such as AdaGrad, RMSProp and Adam are popular owing to their rapid training process. However, theoretical guarantee for the generalization of adaptive optimization algorithms is still lacking. In this paper, we study the implicit regularization of adaptive optimization algorithms when they are optimizing the logistic loss on homogeneous deep neural networks. We prove that adaptive algorithms that adopt exponential moving average strategy in conditioner (such as Adam and RMSProp) can maximize the margin of the neural network, while AdaGrad that directly sums historical squared gradients in conditioner can not. It indicates superiority on generalization of exponential moving average strategy in the design of the conditioner. Technically, we provide a unified framework to analyze convergent direction of adaptive optimization algorithms by constructing novel adaptive gradient flow and surrogate margin. Our experiments can well support the theoretical findings on convergent direction of adaptive optimization algorithms.
