aiqbench analysis
This research introduces Adaptive Policy Backbone (APB), a meta-transfer reinforcement learning method designed to improve sample efficiency and adapt effectively to out-of-distribution tasks using parameter-efficient fine-tuning. By inserting lightweight linear layers around a shared backbone, the approach preserves prior knowledge while overcoming limitations of existing baselines in mismatched environments.
Adaptive Policy Backbone via Shared Network
arXiv:2509.22310v2 Announce Type: replace Abstract: Reinforcement learning (RL) has achieved impressive results across domains, yet learning an optimal policy typically requires extensive interaction data, limiting practical deployment. A common remedy is to leverage priors, such as pre-collected datasets or reference policies, but their utility degrades under task mismatch between training and deployment. While prior work has sought to address this mismatch, it has largely been restricted to in-distribution settings. To address this challenge, we propose Adaptive Policy Backbone (APB), a meta-transfer RL method that inserts lightweight linear layers before and after a shared backbone, thereby enabling parameter-efficient fine-tuning (PEFT) while preserving prior knowledge during adaptation. Our results show that APB improves sample efficiency over standard RL and adapts to out-of-distribution (OOD) tasks where existing meta-RL baselines typically fail.
Abstract:Reinforcement learning (RL) has achieved impressive results across domains, yet learning an optimal policy typically requires extensive interaction data, limiting practical deployment. A common remedy is to leverage priors, such as pre-collected datasets or reference policies, but their utility degrades under task mismatch between training and deployment. While prior work has sought to address this mismatch, it has largely been restricted to in-distribution settings. To address this challenge, we propose Adaptive Policy Backbone (APB), a meta-transfer RL method that inserts lightweight linear layers before and after a shared backbone, thereby enabling parameter-efficient fine-tuning (PEFT) while preserving prior knowledge during adaptation. Our results show that APB improves sample efficiency over standard RL and adapts to out-of-distribution (OOD) tasks where existing meta-RL baselines typically fail.
Machine Learning (cs.LG); Artificial Intelligence (cs.AI)
arXiv:2509.22310 [cs.LG]
(or arXiv:2509.22310v2 [cs.LG] for this version)
https://doi.org/10.48550/arXiv.2509.22310 Focus to learn more arXiv-issued DOI via DataCite
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Full text under the publisher's open licence · 218 words
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