“MuZero Unplugged: Online and Offline Reinforcement Learning by Planning With a Learned Model”, Julian Schrittwieser, Thomas Hubert, Amol Mandhane, Mohammadamin Barekatain, Ioannis Antonoglou, David Silver2021-04-13 (, ; similar)⁠:

Learning efficiently from small amounts of data has long been the focus of model-based reinforcement learning, both for the online case when interacting with the environment and the offline case when learning from a fixed dataset. However, to date no single unified algorithm could demonstrate state-of-the-art results in both settings.

In this work, we describe the Reanalyse algorithm which uses model-based policy and value improvement operators to compute new improved training targets on existing data points, allowing efficient learning for data budgets varying by several orders of magnitude. We further show that Reanalyse can also be used to learn entirely from demonstrations without any environment interactions, as in the case of offline Reinforcement Learning (offline RL).

Combining Reanalyse with the MuZero algorithm, we introduce MuZero Unplugged, a single unified algorithm for any data budget, including offline RL. In contrast to previous work, our algorithm does not require any special adaptations for the off-policy or offline RL settings.

MuZero Unplugged sets new state-of-the-art results in the RL Unplugged offline RL benchmark as well as in the online RL benchmark of Atari ALE in the standard 200 million frame setting.

Figure 1: Final scores in Ms. Pac-Man for different Reanalyse fractions. By scaling the Reanalyse fraction, MuZero can be trained at any desired data budget. All other parameters are held constant. Note the logarithmic x-axis: Linear improvements in score require exponentially more data, matching scaling laws such as described by Kaplan et al 2020 for language models.