POLTER

Policy Trajectory Ensemble Regularization for Unsupervised Reinforcement Learning

verfasst von

Frederik Schubert, Carolin Benjamins, Sebastian Döhler, Bodo Rosenhahn, Marius Lindauer

Abstract

The goal of Unsupervised Reinforcement Learning (URL) is to find a reward-agnostic prior policy on a task domain, such that the sample-efficiency on supervised downstream tasks is improved. Although agents initialized with such a prior policy can achieve a significantly higher reward with fewer samples when finetuned on the downstream task, it is still an open question how an optimal pretrained prior policy can be achieved in practice. In this work, we present POLTER (Policy Trajectory Ensemble Regularization) - a general method to regularize the pretraining that can be applied to any URL algorithm and is especially useful on data- and knowledge-based URL algorithms. It utilizes an ensemble of policies that are discovered during pretraining and moves the policy of the URL algorithm closer to its optimal prior. Our method is based on a theoretical framework, and we analyze its practical effects on a white-box benchmark, allowing us to study POLTER with full control. In our main experiments, we evaluate POLTER on the Unsupervised Reinforcement Learning Benchmark (URLB), which consists of 12 tasks in 3 domains. We demonstrate the generality of our approach by improving the performance of a diverse set of data- and knowledge-based URL algorithms by 19% on average and up to 40% in the best case. Under a fair comparison with tuned baselines and tuned POLTER, we establish a new the state-of-the-art on the URLB.

Organisationseinheit(en)

Institut für Informationsverarbeitung
Forschungszentrum L3S
Fachgebiet Maschinelles Lernen
Fachgebiet Automatische Bildinterpretation

Typ

Artikel

Journal

Transactions on Machine Learning Research

Band

2023

ISSN

2835-8856

Publikationsdatum

04.2023

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

Elektronische Version(en)

https://doi.org/10.48550/arXiv.2205.11357 (Zugang: Offen)
https://openreview.net/pdf?id=Hnr23knZfY (Zugang: Offen)