AIAny
Icon for item

Training Object Permanence in World Models

Provides WROP: a 1.5M-sample synthetic video corpus and a 300-question exam for training and evaluating object permanence and solidity in video world models. Includes 150 Blender task generators, a human Elo benchmark across 14 models, and a fine-tuned 16B continuation model (PWM-WROP).

Introduction

Why this matters

Video generation models are increasingly treated as world models, yet many still violate basic physical priors (objects disappearing behind occluders or passing through solids). WROP demonstrates that these core failures—object permanence and solidity—can be systematically probed and substantially improved by training on cognitively grounded synthetic data and evaluating with human-grounded judgments.

Key Findings
  • Scalable, cognitively inspired data: 150 hand-authored Blender task generators (6 cognitive families) with nuisance randomization, yielding a 1.5M-sample training corpus (≈10k samples per task).
  • Fixed, human-judged exam: a 300-question evaluation set (two questions per generator) judged by pairwise human preferences (Elo) to assess physical-consistency in continuations against hand-authored ground truth.
  • Broad model comparison: 14 video systems evaluated (3 reference-to-video, 7 edit, 4 continuation); PWM-WROP, a 16B continuation model fine-tuned on WROP, ranks first among continuation models in a blind human Elo study.
  • Reproducible research artifacts: releases include the training corpus, the exam and model answers, model weights (PWM-WROP), the Blender generators, and a native-PyTorch training stack for AWS Trainium2, enabling controlled experiments on physical reasoning.
  • Empirical tradeoffs: at native low resolution (320×192) PWM-WROP matches or exceeds continuation baselines on LPIPS and MS-SSIM when resolution-matched, but commercial reference-to-video systems remain competitive at higher native resolutions.
Methodological notes

Each sample splits a clip at the key physical event: the model receives the input half (ending at or just before occlusion/containment) and must predict the subsequent half where the occluded object's fate is resolved. Generators randomize lighting, speed, camera angle and other nuisances while preserving the cognitive structure, enabling generalization tests and per-sample metadata for analysis.

Who it's for and tradeoffs

Great fit if you want a controlled, cognitively grounded benchmark and dataset to train or evaluate video world models on physical reasoning (object permanence/solidity), reproduce human-preference evaluations, or fine-tune continuation architectures. Look elsewhere if your primary need is photorealistic, high-resolution real-world footage (domain gap from Blender may limit direct transfer), if you require purely automated VLM-based judging for subtle core-knowledge tasks, or if you need native high-resolution continuity without additional upscaling.

Information

  • Websitearxiv.org
  • OrganizationsUniversity of Southern California, Carnegie Mellon University, University of Michigan, Johns Hopkins University, University of California, San Diego, University of California, Los Angeles, Columbia University, University of Toronto, University of Bristol, University of California, Berkeley, University of Waterloo, Friedrich-Alexander-Universität Erlangen, University of Oxford, New York University, Stanford University, Harvard University
  • AuthorsHaotian Zhang, Fengyuan Yu, Dezhi Luo, Haoran Sun, Zehong Zhao, Qingying Gao, Yihan Li, Siyuan An, Huayi Qin, Yilan Zhang …
  • Published date2026/09/23

More Items

Hugging Face

Provides 1,800+ hours of synchronized egocentric multi-view recordings with 3D hand reconstructions, wide‑FOV depth, and hierarchical task/subtask annotations for embodied AI and robot learning. Includes six fisheye views, hand meshes, and per-episode temporal labels across 44k+ episodes.

Hugging Face

Provides 10,000 agentic multi-turn coding and reasoning traces from Fable 5.1 with step-by-step chain-of-thought and tool-use, heavily deduplicated and filtered; totals ~500M tokens (1.97 GB). Suited for SFT, distillation, and training long-horizon reasoning and code-generation models.

Introduces a rubric-based approach for video reward modeling that generates explicit, query-adaptive evaluation criteria before scoring to reduce scalar drift; proposes RGPO, a two-stage training (seed warm-up + joint optimization) that achieves strong pointwise and pairwise evaluation with high data efficiency.