Papers › Learning from Sparse Offline Datasets via Conservative Density Estimation

Learning from Sparse Offline Datasets via Conservative Density Estimation

16 Jan 2024arXiv:2401.08819archive 2025-07-28

Zhepeng Cen, Zuxin Liu, Zitong Wang, Yihang Yao, Henry Lam, Ding Zhao

Offline reinforcement learning (RL) offers a promising direction for learning policies from pre-collected datasets without requiring further interactions with the environment. However, existing methods struggle to handle out-of-distribution (OOD) extrapolation errors, especially in sparse reward or scarce data settings. In this paper, we propose a novel training algorithm called Conservative Density Estimation (CDE), which addresses this challenge by explicitly imposing constraints on the state-action occupancy stationary distribution. CDE overcomes the limitations of existing approaches, such as the stationary distribution correction method, by addressing the support mismatch issue in marginal importance sampling. Our method achieves state-of-the-art performance on the D4RL benchmark. Notably, CDE consistently outperforms baselines in challenging tasks with sparse rewards or insufficient data, demonstrating the advantages of our approach in addressing the extrapolation error problem in offline RL.

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CDELearner czp16/cde-offline-rl/cde.py official repository ran MIT (permissive) · 1df7301b0c11658e · report
get_f_div_fn czp16/cde-offline-rl/cde.py official repository ran · our draft was wrong MIT (permissive) · e06c8c099e9fd7f4 · report
to_tensor czp16/cde-offline-rl/cde.py official repository ran · honoured contract fingerprinted MIT (permissive) · cb62199e8e3037a1 · report
Config czp16/cde-offline-rl/cde.py official repository unverified MIT (permissive) · 731a435187750caf · report

Tasks

D4RLDensity EstimationOffline RLReinforcement Learning (RL)

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