Just Cluster It: An Approach for Exploration in High-Dimensions using Clustering and Pre-Trained Representations

Stefan Sylvius Wagner; Stefan Harmeling

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arXiv · 2402.03138

Just Cluster It: An Approach for Exploration in High-Dimensions using Clustering and Pre-Trained Representations

Stefan Sylvius Wagner·Stefan Harmeling

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Abstract

In this paper we adopt a representation-centric perspective on exploration in reinforcement learning, viewing exploration fundamentally as a density estimation problem. We investigate the effectiveness of clustering representations for exploration in 3-D environments, based on the observation that the importance of pixel changes between transitions is less pronounced in 3-D environments compared to 2-D environments, where pixel changes between transitions are typically distinct and significant. We propose a method that performs episodic and global clustering on random representations and on pre-trained DINO representations to count states, i.e, estimate pseudo-counts. Surprisingly, even random features can be clustered effectively to count states in 3-D environments, however when these become visually more complex, pre-trained DINO representations are more effective thanks to the pre-trained inductive biases in the representations. Overall, this presents a pathway for integrating pre-trained biases into exploration. We evaluate our approach on the VizDoom and Habitat environments, demonstrating that our method surpasses other well-known exploration methods in these settings.

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BibTeX RIS

Stefan Sylvius Wagner, Stefan Harmeling. 2024-08-14. Just Cluster It: An Approach for Exploration in High-Dimensions using Clustering and Pre-Trained Representations. https://arxiv.org/abs/2402.03138

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