aspireai.
PUBLIC EDITION

A hierarchical world model split planning from control and gained 135 percent over flat MPC

AspireAI community · arXiv (cs.RO, cs.AI)
ID-WM, from a team including Yann LeCun, decouples state-space reachability from local control: a high-level model samples feasible transitions across the state manifold while a low-level world model acts as an inverse dynamics solver that grounds those transitions into precise actions. Because the planner no longer has to reason about execution detail, the authors report a 38.5 percent improvement over state-of-the-art policy and diffusion-based planners across three navigation and manipulation suites, and a 135 percent gain over single-level world-model model predictive control on long-horizon tasks in complex, unseen configurations. The honest limit is scope: the evaluation covers three suites, and the claim is that the hierarchical structure mitigates compounding error rather than removing it.
Read the story and explore more from the AspireAI community.
Discover more stories
Stay curious.
THE BIG PICTURE
A FRESH PERSPECTIVE
Research
One distance function matched sparse-autoencoder features across layers and compressed feature circuits into supernodes
Two sparse-autoencoder analyses have resisted scaling: matching semantically similar features across layers, and compressing large feature circuits into interpretable supernodes. This paper argues both are the same underlying problem, estimating semantic distances between SAE features that sit on different activation manifolds. Its representation treats each feature not as a single decoder vector but as an activation-weighted distribution over the hidden states expressing it, projects those distributions into a shared reference space, and compares them with Wasserstein distance. The representation is proved invariant to activation rescaling and stable under perturbation, and recovers true matches under finite-sample margin conditions. Empirically it outperformed decoder-vector and LLM-based baselines and captured subtle functional distinctions between related features, and it compressed large feature circuits into interpretable supernodes automatically. The limitation is that this is interpretability tooling: the paper demonstrates better feature matching and circuit compression, not that downstream interpretability claims become more accurate.
Swipe into something new
01 / 1729
The conversation continues
Explore Builds — projects by Kiran Adimatyam ↗
A fresh perspective changes everything.
ASPIREAI — STAY CURIOUS.