Papers › Skill Expansion and Composition in Parameter Space

Skill Expansion and Composition in Parameter Space

9 Feb 2025arXiv:2502.05932archive 2025-07-28

Tenglong Liu, Jianxiong Li, Yinan Zheng, Haoyi Niu, Yixing Lan, Xin Xu, Xianyuan Zhan

Humans excel at reusing prior knowledge to address new challenges and developing skills while solving problems. This paradigm becomes increasingly popular in the development of autonomous agents, as it develops systems that can self-evolve in response to new challenges like human beings. However, previous methods suffer from limited training efficiency when expanding new skills and fail to fully leverage prior knowledge to facilitate new task learning. In this paper, we propose Parametric Skill Expansion and Composition (PSEC), a new framework designed to iteratively evolve the agents' capabilities and efficiently address new challenges by maintaining a manageable skill library. This library can progressively integrate skill primitives as plug-and-play Low-Rank Adaptation (LoRA) modules in parameter-efficient finetuning, facilitating efficient and flexible skill expansion. This structure also enables the direct skill compositions in parameter space by merging LoRA modules that encode different skills, leveraging shared information across skills to effectively program new skills. Based on this, we propose a context-aware module to dynamically activate different skills to collaboratively handle new tasks. Empowering diverse applications including multi-objective composition, dynamics shift, and continual policy shift, the results on D4RL, DSRL benchmarks, and the DeepMind Control Suite show that PSEC exhibits superior capacity to leverage prior knowledge to efficiently tackle new challenges, as well as expand its skill libraries to evolve the capabilities. Project website: https://ltlhuuu.github.io/PSEC/.

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2ran · violated contract
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compute_q ltlhuuu/PSEC/jaxrl5/agents/psec/psec_finetune.py official repository ran · fixture could not drive it MIT (permissive) · efbad980c5e8e094 · report
cosine_beta_schedule ltlhuuu/PSEC/jaxrl5/networks/diffusion.py official repository ran · honoured contract fingerprinted MIT (permissive) · 87d1bc442d93916d · report
expectile_loss ltlhuuu/PSEC/jaxrl5/agents/psec/psec_finetune.py official repository ran · violated contract fingerprinted MIT (permissive) · ad221b0896e1bcd0 · report
get_weight_decay_mask ltlhuuu/PSEC/jaxrl5/networks/mlp.py official repository ran MIT (permissive) · 1049990078a4b0f2 · report
linear_beta_schedule ltlhuuu/PSEC/jaxrl5/networks/diffusion.py official repository ran MIT (permissive) · 0cd44ae2231fcb3b · report
mish ltlhuuu/PSEC/jaxrl5/agents/psec/psec_pretrain.py official repository ran · honoured contract fingerprinted MIT (permissive) · 7fc1d127bf81537f · report
safe_expectile_loss ltlhuuu/PSEC/jaxrl5/agents/psec/psec_finetune.py official repository ran · violated contract fingerprinted MIT (permissive) · 7e821a429b5ff00e · report
vp_beta_schedule ltlhuuu/PSEC/jaxrl5/networks/diffusion.py official repository ran · honoured contract fingerprinted MIT (permissive) · 539aaf559a17a19a · report
evaluate ltlhuuu/PSEC/jaxrl5/evaluation_dsrl.py official repository unverified MIT (permissive) · 27b1370715ab6f72 · report
evaluate1 ltlhuuu/PSEC/jaxrl5/evaluation_dsrl.py official repository unverified MIT (permissive) · 74b0ae56402911be · report
evaluate2 ltlhuuu/PSEC/jaxrl5/evaluation_dsrl.py official repository unverified MIT (permissive) · c7143d30af7311f2 · report
subsample_ensemble ltlhuuu/PSEC/jaxrl5/networks/ensemble.py official repository unverified MIT (permissive) · c021b9fd8bb7677d · report

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