On the model-based stochastic value gradient for continuous reinforcement learning

Learning for Dynamics & Control Conference (L4DC)

Abstract

For over a decade, model-based reinforcement learning has been seen as a way to leverage control-based domain knowledge to improve the sample-efficiency of reinforcement learning agents. While model-based agents are conceptually appealing, their policies tend to lag behind those of model-free agents in terms of final reward, especially in non-trivial environments. In response, researchers have proposed model-based agents with increasingly complex components, from ensembles of probabilistic dynamics models, to heuristics for mitigating model error. In a reversal of this trend, we show that simple model-based agents can be derived from existing ideas that not only match, but outperform state-of-the-art model-free agents in terms of both sample-efficiency and final reward. We find that a model-free soft value estimate for policy evaluation and a model-based stochastic value gradient for policy improvement is an effective combination, achieving state-of-the-art results on a high-dimensional humanoid control task, which most model-based agents are unable to solve. Our findings suggest that model-based policy evaluation deserves closer attention. The source code to reproduce our experiments is available online at: https://github.com/facebookresearch/svg.

Latest Publications

Log-structured Protocols in Delos

Mahesh Balakrishnan, Mahesh Balakrishnan, Mihir Dharamshi, Jason Flinn, David Geraghty, Santosh Ghosh, Filip Gruszczynski, Ahmed Jafri, Jun Li, Jingming Liu, Suyog Mapara, Rajeev Nagar, Ivailo Nedelchev, Francois Richard, Chen Shen, Yee Jiun Song, Rounak Tibrewal, Vidhya Venkat, Ahmed Yossef, Ali Zaveri

SOSP