arXiv Machine Learning

Biased Dreams: Limitations to Epistemic Uncertainty Quantification in Latent Dynamics Models

arXiv:2604. 25416v2 Announce Type: replace Abstract: Model-based reinforcement learning distinguishes between dynamics models operating on proprioceptive states and latent dynamics models typically operating on high-dimensional image observations.

arXiv Machine Learning
Jul 23

Koopman Dreamer: Spectrally Constrained Latent Dynamics for Stable World-Model Imagination

arXiv:2607. 19719v1 Announce Type: new Abstract: Latent world models improve sample efficiency in continuous control by optimizing policies over imagined latent trajectories, but common neural transitions offer limited direct control over modal persistence and error accumulation in long rollouts.

By Jiaqi Li, Xinglong Zhang, Haibin Xie, Yixing Lan, Wei Pan, Xin Xu
arXiv Machine Learning
Sep 21

Adaptive Rollout Truncation Based on Epistemic Uncertainty for Efficient Offline World Model Training

The paper introduces an adaptive rollout truncation method for offline world model training that uses epistemic uncertainty to decide when to stop autoregressive rollouts. By calibrating a threshold during a warm‑up phase, the approach replaces fixed‑horizon rollouts with uncertainty‑driven truncation, evaluated with ensemble and Monte Carlo dropout estimators. Experiments on ANYmal‑D and ANT demonstrate that this strategy matches or surpasses fixed‑horizon training while reducing cumulative rollout steps by about 72%.

By Nikodem Sebastian Zymla, Laurin Thiele, Johannes Pitz
arXiv Machine Learning
Sep 22

Contrastive World Models

Contrastive World Models propose a new method for learning latent dynamics without pixel reconstruction. By replacing observation reconstruction with a Deep InfoMax-like objective that maximizes mutual information between state-action sequences and local patch features of future observations, the approach encourages state representations to retain predictive information while ignoring visually irrelevant details. Experiments show that this method matches existing baselines in simple settings and significantly outperforms them when distractors or natural video backgrounds are present, while also training more efficiently by eliminating the pixel decoder.

By Bonnie Li
arXiv AI
2d ago

Measuring the Stability Assumption Behind Action Chunking

The paper investigates how small action errors evolve when using action chunking in behavioural cloning. By injecting errors at each state and observing their growth under open‑loop (no replanning) and closed‑loop (replanning) regimes, the authors classify states as contracting, expanding, or unresolved. Across twelve manipulation tasks, they find that stable states are rare, error amplification is common, and that short‑horizon fitting can overestimate long‑horizon propagation. Predictors trained on camera and proprioceptive data can recover open‑loop stability but only partially capture closed‑loop dynamics, indicating that standard imitation learning does not reliably produce policies that contract errors when perturbed.

By Aryan Goyal
arXiv Machine Learning
Jul 14

A Control Theory of Predictability in Latent World Models

arXiv:2607. 10362v1 Announce Type: new Abstract: Latent world models are trained to predict future states in a learned representation and are then deployed inside a planner that selects actions by simulating them forward.

By Hanzhe You, Yonggang Zhang, Maohao Ran, Zhiqin Yang, Zhenyuan Zhang, Wei Xue, Jun Song, Xinmei Tian, Yike Guo