Bilevel reinforcement learning via the development of hyper-gradient without lower-level convexity
On the map: Deep reinforcement learning methods → RL theory and sample complexity
Abstract (arXiv)
Bilevel reinforcement learning (RL), which features intertwined two-level problems, has attracted growing interest recently. The inherent non-convexity of the lower-level RL problem is, however, to be an impediment to developing bilevel optimization methods. By employing the fixed point equation associated with the regularized RL, we characterize the hyper-gradient via fully first-order information, thus circumventing the assumption of lower-level convexity. This, remarkably, distinguishes our development of hyper-gradient from the general AID-based bilevel frameworks since we take advantage of the specific structure of RL problems. Moreover, we design both model-based and model-free bilevel reinforcement learning algorithms, facilitated by access to the fully first-order hyper-gradient. Both algorithms enjoy the convergence rate O(ε-1). To extend the applicability, a stochastic version of the model-free algorithm is proposed, along with results on its iteration and sample complexity. In addition, numerical experiments demonstrate that the hyper-gradient indeed serves as an integration of exploitation and exploration.
Key facts. Cited by 10 papers in the map (data through 14 Oct 2026). Placed in RL theory and sample complexity, one of 15 directions in Deep reinforcement learning methods. Builds on 68 of its 85 references that are in the map. First posted on arXiv 30 May 2024.
Builds on
68 of 85 references.
References · 68
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38 more
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50 most cited of 68 All 68 (JSON)
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Citing papers per year: 2024: 1; 2025: 2; 2026: 7.
10 papers.
- 2025On The Sample Complexity Bounds In Bilevel Reinforcement Learningcited by 10
- 2024BiSSL: Enhancing the Alignment Between Self-Supervised Pretraining and Downstream Fine-Tuning via Bilevel Optimizationcited by 3
- 2026Sample-Efficient Hypergradient Estimation for Decentralized Bi-Level Reinforcement Learningcited by 2
- 2026Penalty-Based First-Order Methods for Bilevel Optimization with Minimax and Constrained Lower-Level Problemscited by 1
- 2026On the Convergence of Self-Improving Online LLM Alignmentcited by 1
- 2025From Data to Rewards: a Bilevel Optimization Perspective on Maximum Likelihood Estimationcited by 0
- 2026Sample Complexity Analysis for Constrained Bilevel Reinforcement Learningcited by 0
- 2026Hypergradient-based Bilevel Reinforcement Learning with Improved Sample Complexitycited by 0
- 2026Efficient Hypergradient Descent for Inverse Reinforcement Learningcited by 0
- 2026Learning the Robustness Mechanism with Bilevel Optimizationcited by 0
- 2026Learning the Robustness Mechanism with Bilevel Optimization28 Sep 2026
- 2026Efficient Hypergradient Descent for Inverse Reinforcement Learning11 Aug 2026
- 2026Hypergradient-based Bilevel Reinforcement Learning with Improved Sample Complexity30 Jul 2026
- 2026On the Convergence of Self-Improving Online LLM Alignment30 Jun 2026
- 2026Penalty-Based First-Order Methods for Bilevel Optimization with Minimax and Constrained Lower-Level Problems8 May 2026
- 2026Sample-Efficient Hypergradient Estimation for Decentralized Bi-Level Reinforcement Learning16 Mar 2026
- 2026Sample Complexity Analysis for Constrained Bilevel Reinforcement Learning30 Jan 2026
- 2025From Data to Rewards: a Bilevel Optimization Perspective on Maximum Likelihood Estimation8 Oct 2025
- 2025On The Sample Complexity Bounds In Bilevel Reinforcement Learning22 Mar 2025
- 2024BiSSL: Enhancing the Alignment Between Self-Supervised Pretraining and Downstream Fine-Tuning via Bilevel Optimization3 Oct 2024
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- 2024A Communication and Computation Efficient Fully First-order Method for Decentralized Bilevel Optimization
- 2026A Hessian-Free Actor-Critic Algorithm for Bi-Level Reinforcement Learning with Applications to LLM Fine-Tuning
- 2024Meta-Reinforcement Learning with Universal Policy Adaptation: Provable Near-Optimality under All-task Optimum Comparator
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