titleYoCausal: How Far is Video Generation from World Model? A Causality Perspective
authorsYou-Zhe Xie, Yu-Hsuan Li, Jie-Ying Lee, Kaipeng Zhang, Yu-Lun Liu, Zhixiang Wang
date2026-05-28
venuearXiv (preprint, not peer reviewed)
idarXiv:2605.30346
affiliationAlaya Lab
upvotes49 (Hugging Face Daily Papers, 2026-11-01)
linksabs pdf hf code
primerWorld models
abstractAs video diffusion models (VDMs) advance toward world models, a key question arises: do they truly understand causality, or merely overfit to statistical temporal patterns? Existing benchmarks mostly rely on synthetic data, limiting real-world generalization due to the sim-to-real gap. We present YoCausal, a two-level benchmark inspired by the Violation of Expectation (VoE) paradigm from cognitive science. By temporally reversing real-world videos at zero cost as natural counterfactual samples, YoCausal establishes an arbitrarily extensible evaluation protocol. Level 1 introduces the Reverse Surprise Index (RSI), quantifying arrow-of-time perception via denoising loss. Level 2 introduces the Causality Cognition Index (CCI), which leverages a VLM to stratify datasets into causal and non-causal subsets, disentangling genuine causal reasoning from temporal bias. Evaluation of 13 state-of-the-art VDMs reveals that perceiving the arrow of time does not imply understanding causality, and a significant gap persists relative to human-level causal cognition.

cite

@misc{xie2026yocausal,
  title={YoCausal: How Far is Video Generation from World Model? A Causality Perspective},
  author={You-Zhe Xie and Yu-Hsuan Li and Jie-Ying Lee and Kaipeng Zhang and Yu-Lun Liu and Zhixiang Wang},
  year={2026},
  eprint={2605.30346},
  archivePrefix={arXiv},
  url={https://arxiv.org/abs/2605.30346}
}