Learning Causal Dynamics Models in Object-Oriented Environments
Zhongwei Yu, Jingqing Ruan, Dengpeng Xing
TL;DR
The paper tackles scalable learning of causal dynamics in large-scale object-oriented environments by proposing OOCDM, which shares causal structure and predictors across objects of the same class. It formalizes an Object-Oriented Canonical Graph (OOCG), develops class-shared field predictors with attention, and introduces a class-level causal discovery mechanism using CMIs. The approach dramatically reduces causal-discovery complexity, improves graph and predictive accuracy, and enhances generalization and planning performance, especially in tasks with many objects or varying instance counts. Augmentations to handle asymmetric dynamics extend applicability beyond strictly symmetric OO settings, positioning OOCDM as a practical framework for scalable, causality-aware world models in RL.
Abstract
Causal dynamics models (CDMs) have demonstrated significant potential in addressing various challenges in reinforcement learning. To learn CDMs, recent studies have performed causal discovery to capture the causal dependencies among environmental variables. However, the learning of CDMs is still confined to small-scale environments due to computational complexity and sample efficiency constraints. This paper aims to extend CDMs to large-scale object-oriented environments, which consist of a multitude of objects classified into different categories. We introduce the Object-Oriented CDM (OOCDM) that shares causalities and parameters among objects belonging to the same class. Furthermore, we propose a learning method for OOCDM that enables it to adapt to a varying number of objects. Experiments on large-scale tasks indicate that OOCDM outperforms existing CDMs in terms of causal discovery, prediction accuracy, generalization, and computational efficiency.
