Papers › Mastering Memory Tasks with World Models

Mastering Memory Tasks with World Models

7 Mar 2024arXiv:2403.04253archive 2025-07-28

Mohammad Reza Samsami, Artem Zholus, Janarthanan Rajendran, Sarath Chandar

Current model-based reinforcement learning (MBRL) agents struggle with long-term dependencies. This limits their ability to effectively solve tasks involving extended time gaps between actions and outcomes, or tasks demanding the recalling of distant observations to inform current actions. To improve temporal coherence, we integrate a new family of state space models (SSMs) in world models of MBRL agents to present a new method, Recall to Imagine (R2I). This integration aims to enhance both long-term memory and long-horizon credit assignment. Through a diverse set of illustrative tasks, we systematically demonstrate that R2I not only establishes a new state-of-the-art for challenging memory and credit assignment RL tasks, such as BSuite and POPGym, but also showcases superhuman performance in the complex memory domain of Memory Maze. At the same time, it upholds comparable performance in classic RL tasks, such as Atari and DMC, suggesting the generality of our method. We also show that R2I is faster than the state-of-the-art MBRL method, DreamerV3, resulting in faster wall-time convergence.

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cast_to_compute chandar-lab/Recall2Imagine/recall2imagine/jaxutils.py official repository ran MIT (permissive) · ed94f4331173c9bc · report
pure chandar-lab/Recall2Imagine/recall2imagine/ninjax.py official repository ran MIT (permissive) · bbd25fa32893729e · report
subsample chandar-lab/Recall2Imagine/recall2imagine/jaxutils.py official repository ran MIT (permissive) · e5b1910ea05891b1 · report
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convert chandar-lab/Recall2Imagine/recall2imagine/embodied/core/basics.py official repository unverified MIT (permissive) · 4b830637b16db4c8 · report
format_ chandar-lab/Recall2Imagine/recall2imagine/embodied/core/basics.py official repository unverified MIT (permissive) · 3360b32511bc42d4 · report
get_act chandar-lab/Recall2Imagine/recall2imagine/nets.py official repository unverified MIT (permissive) · 03dd934385b4d240 · report
grad chandar-lab/Recall2Imagine/recall2imagine/ninjax.py official repository unverified MIT (permissive) · 1ad869363216c281 · report
init_mimo_ssm chandar-lab/Recall2Imagine/recall2imagine/ssm_nets.py official repository unverified MIT (permissive) · ce9e0c5374238d06 · report
init_siso_ssm chandar-lab/Recall2Imagine/recall2imagine/ssm_nets.py official repository unverified MIT (permissive) · ad8b4b5ddd9df92c · report
rng chandar-lab/Recall2Imagine/recall2imagine/ninjax.py official repository unverified MIT (permissive) · 45b97b51433849a7 · report
treemap chandar-lab/Recall2Imagine/recall2imagine/embodied/core/basics.py official repository unverified MIT (permissive) · 5ba274a4e18b46f3 · report

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