# Online Meta-Critic Learning for Off-Policy Actor-Critic Methods

arXiv: https://arxiv.org/abs/2003.05334 · HTML: https://mlsanity.com/paper/2003.05334/

## Key facts

- Cited by 17 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 11 Mar 2020.

## Built on by (most cited first, 17 of 17)

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- [Improved Robustness and Safety for Pre-Adaptation of Meta Reinforcement Learning with Prior Regularization](https://mlsanity.com/paper/2108.08448/) (2021)
- [Credit Assignment with Meta-Policy Gradient for Multi-Agent Reinforcement Learning](https://mlsanity.com/paper/2102.12957/) (2021)
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- [Black Box Meta-Learning Intrinsic Rewards](https://mlsanity.com/paper/2407.21546/) (2024)
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- [MetaCon: Unified Predictive Segments System with Trillion Concept Meta-Learning](https://mlsanity.com/paper/2203.04540/) (2022)
- [Model Based Meta Learning of Critics for Policy Gradients](https://mlsanity.com/paper/2204.02210/) (2022)
- [Multi-agent Off-policy Actor-Critic Reinforcement Learning for Partially Observable Environments](https://mlsanity.com/paper/2407.04974/) (2024)
- [Enhancing Online Reinforcement Learning with Meta-Learned Objective from Offline Data](https://mlsanity.com/paper/2501.07346/) (2025)
- [Meta-reinforcement learning with minimum attention](https://mlsanity.com/paper/2505.16741/) (2025)

## Abstract (arXiv)

Off-Policy Actor-Critic (Off-PAC) methods have proven successful in a variety of continuous control tasks. Normally, the critic's action-value function is updated using temporal-difference, and the critic in turn provides a loss for the actor that trains it to take actions with higher expected return. In this paper, we introduce a novel and flexible meta-critic that observes the learning process and meta-learns an additional loss for the actor that accelerates and improves actor-critic learning. Compared to the vanilla critic, the meta-critic network is explicitly trained to accelerate the learning process; and compared to existing meta-learning algorithms, meta-critic is rapidly learned online for a single task, rather than slowly over a family of tasks. Crucially, our meta-critic framework is designed for off-policy based learners, which currently provide state-of-the-art reinforcement learning sample efficiency. We demonstrate that online meta-critic learning leads to improvements in avariety of continuous control environments when combined with contemporary Off-PAC methods DDPG, TD3 and the state-of-the-art SAC.
