# BiAdam: Fast Adaptive Bilevel Optimization Methods

arXiv: https://arxiv.org/abs/2106.11396 · HTML: https://mlsanity.com/paper/2106.11396/

## Key facts

- Cited by 33 papers in the map (data through 14 Oct 2026).
- Builds on 24 of its 47 references that are in the map.
- First posted on arXiv 21 Jun 2021.

## Builds on (most cited first, 24 of 24)

- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [DARTS: Differentiable Architecture Search](https://mlsanity.com/paper/1806.09055/) (2018)
- [On the Convergence of Adam and Beyond](https://mlsanity.com/paper/1904.09237/) (2019)
- [Bilevel Programming for Hyperparameter Optimization and Meta-Learning](https://mlsanity.com/paper/1806.04910/) (2018)
- [SAGA: A Fast Incremental Gradient Method With Support for Non-Strongly Convex Composite Objectives](https://mlsanity.com/paper/1407.0202/) (2014)
- [Momentum-Based Variance Reduction in Non-Convex SGD](https://mlsanity.com/paper/1905.10018/) (2019)
- [AdaBelief Optimizer: Adapting Stepsizes by the Belief in Observed Gradients](https://mlsanity.com/paper/2010.07468/) (2020)
- [Approximation Methods for Bilevel Programming](https://mlsanity.com/paper/1802.02246/) (2018)
- [Bilevel Optimization: Convergence Analysis and Enhanced Design](https://mlsanity.com/paper/2010.07962/) (2020)
- [Truncated Back-propagation for Bilevel Optimization](https://mlsanity.com/paper/1810.10667/) (2018)
- [AdaGrad stepsizes: Sharp convergence over nonconvex landscapes](https://mlsanity.com/paper/1806.01811/) (2018)
- [On the Convergence of A Class of Adam-Type Algorithms for Non-Convex Optimization](https://mlsanity.com/paper/1808.02941/) (2018)
- [On the Convergence of Stochastic Gradient Descent with Adaptive Stepsizes](https://mlsanity.com/paper/1805.08114/) (2018)
- [On the Iteration Complexity of Hypergradient Computation](https://mlsanity.com/paper/2006.16218/) (2020)
- [Investigating Bi-Level Optimization for Learning and Vision from a Unified Perspective: A Survey and Beyond](https://mlsanity.com/paper/2101.11517/) (2021)
- [A Two-Timescale Framework for Bilevel Optimization: Complexity Analysis and Application to Actor-Critic](https://mlsanity.com/paper/2007.05170/) (2020)
- [Mini-batch Stochastic Approximation Methods for Nonconvex Stochastic Composite Optimization](https://mlsanity.com/paper/1308.6594/) (2013)
- [A Near-Optimal Algorithm for Stochastic Bilevel Optimization via Double-Momentum](https://mlsanity.com/paper/2102.07367/) (2021)
- [Provably Faster Algorithms for Bilevel Optimization](https://mlsanity.com/paper/2106.04692/) (2021)
- [Closing the Generalization Gap of Adaptive Gradient Methods in Training Deep Neural Networks](https://mlsanity.com/paper/1806.06763/) (2018)
- [A Single-Timescale Method for Stochastic Bilevel Optimization](https://mlsanity.com/paper/2102.04671/) (2021)
- [Lower Bounds and Accelerated Algorithms for Bilevel Optimization](https://mlsanity.com/paper/2102.03926/) (2021)
- [SUPER-ADAM: Faster and Universal Framework of Adaptive Gradients](https://mlsanity.com/paper/2106.08208/) (2021)
- [A General Descent Aggregation Framework for Gradient-based Bi-level Optimization](https://mlsanity.com/paper/2102.07976/) (2021)

## Built on by (most cited first, 30 of 33)

- [A Fully First-Order Method for Stochastic Bilevel Optimization](https://mlsanity.com/paper/2301.10945/) (2023)
- [A framework for bilevel optimization that enables stochastic and global variance reduction algorithms](https://mlsanity.com/paper/2201.13409/) (2022)
- [FedNest: Federated Bilevel, Minimax, and Compositional Optimization](https://mlsanity.com/paper/2205.02215/) (2022)
- [A Fully Single Loop Algorithm for Bilevel Optimization without Hessian Inverse](https://mlsanity.com/paper/2112.04660/) (2021)
- [First-order penalty methods for bilevel optimization](https://mlsanity.com/paper/2301.01716/) (2023)
- [Enhanced Bilevel Optimization via Bregman Distance](https://mlsanity.com/paper/2107.12301/) (2021)
- [Bilevel Optimization with a Lower-level Contraction: Optimal Sample Complexity without Warm-start](https://mlsanity.com/paper/2202.03397/) (2022)
- [Imperative Learning: A Self-supervised Neuro-Symbolic Learning Framework for Robot Autonomy](https://mlsanity.com/paper/2406.16087/) (2024)
- [Online Bilevel Optimization: Regret Analysis of Online Alternating Gradient Methods](https://mlsanity.com/paper/2207.02829/) (2022)
- [On Momentum-Based Gradient Methods for Bilevel Optimization with Nonconvex Lower-Level](https://mlsanity.com/paper/2303.03944/) (2023)
- [SimFBO: Towards Simple, Flexible and Communication-efficient Federated Bilevel Learning](https://mlsanity.com/paper/2305.19442/) (2023)
- [AdaGDA: Faster Adaptive Gradient Descent Ascent Methods for Minimax Optimization](https://mlsanity.com/paper/2106.16101/) (2021)
- [Communication-Efficient Federated Hypergradient Computation via Aggregated Iterative Differentiation](https://mlsanity.com/paper/2302.04969/) (2023)
- [Communication-Efficient Robust Federated Learning with Noisy Labels](https://mlsanity.com/paper/2206.05558/) (2022)
- [Projection-Free Algorithm for Stochastic Bi-level Optimization](https://mlsanity.com/paper/2110.11721/) (2021)
- [Communication-Efficient Federated Bilevel Optimization with Local and Global Lower Level Problems](https://mlsanity.com/paper/2302.06701/) (2023)
- [Fast Adaptive Federated Bilevel Optimization](https://mlsanity.com/paper/2211.01122/) (2022)
- [Rethinking Adam: A Twofold Exponential Moving Average Approach](https://mlsanity.com/paper/2106.11514/) (2021)
- [Non-asymptotic Analysis of Biased Adaptive Stochastic Approximation](https://mlsanity.com/paper/2402.02857/) (2024)
- [CoBo: Collaborative Learning via Bilevel Optimization](https://mlsanity.com/paper/2409.05539/) (2024)
- [Tuning-Free Bilevel Optimization: New Algorithms and Convergence Analysis](https://mlsanity.com/paper/2410.05140/) (2024)
- [BiSLS/SPS: Auto-tune Step Sizes for Stable Bi-level Optimization](https://mlsanity.com/paper/2305.18666/) (2023)
- [Solving bilevel optimization via sequential minimax optimization](https://mlsanity.com/paper/2511.07398/) (2025)
- [Faster Adaptive Momentum-Based Federated Methods for Distributed Composition Optimization](https://mlsanity.com/paper/2211.01883/) (2022)
- [Adaptive Mirror Descent Bilevel Optimization](https://mlsanity.com/paper/2311.04520/) (2023)
- [Achieving O(ε-1.5) Complexity in Hessian/Jacobian-free Stochastic Bilevel Optimization](https://mlsanity.com/paper/2312.03807/) (2023)
- [Online Nonconvex Bilevel Optimization with Bregman Divergences](https://mlsanity.com/paper/2409.10470/) (2024)
- [Adaptive Algorithms with Sharp Convergence Rates for Stochastic Hierarchical Optimization](https://mlsanity.com/paper/2509.15399/) (2025)
- [On the Convergence of Momentum-Based Algorithms for Federated Bilevel Optimization Problems](https://mlsanity.com/paper/2204.13299/) (2022)
- [Gradient-Free Method for Heavily Constrained Nonconvex Optimization](https://mlsanity.com/paper/2409.00459/) (2024)

## Abstract (arXiv)

Bilevel optimization recently has attracted increased interest in machine learning due to its many applications such as hyper-parameter optimization and meta learning. Although many bilevel methods recently have been proposed, these methods do not consider using adaptive learning rates. It is well known that adaptive learning rates can accelerate optimization algorithms. To fill this gap, in the paper, we propose a novel fast adaptive bilevel framework to solve stochastic bilevel optimization problems that the outer problem is possibly nonconvex and the inner problem is strongly convex. Our framework uses unified adaptive matrices including many types of adaptive learning rates, and can flexibly use the momentum and variance reduced techniques. In particular, we provide a useful convergence analysis framework for the bilevel optimization. Specifically, we propose a fast single-loop adaptive bilevel optimization (BiAdam) algorithm, which achieves a sample complexity of tildeO(ε-4) for finding an ε-stationary solution. Meanwhile, we propose an accelerated version of BiAdam algorithm (VR-BiAdam), which reaches the best known sample complexity of tildeO(ε-3). To the best of our knowledge, we first study the adaptive bilevel optimization methods with adaptive learning rates. Experimental results on data hyper-cleaning and hyper-representation learning tasks demonstrate the efficiency of our algorithms.
