Generative video models demonstrate impressive text-to-video capabilities,
spurring widespread adoption in many real-world applications. However, like
large language models (LLMs), video generation models tend to hallucinate,
producing plausible videos even when they are factually wrong. Although
uncertainty quantification (UQ) of LLMs has been extensively studied in prior
work, no UQ method for video models exists, raising critical safety concerns.
To our knowledge, this paper represents the first work towards quantifying the
uncertainty of video models. We present a framework for uncertainty
quantification of generative video models, consisting of: (i) a metric for
evaluating the calibration of video models based on robust rank correlation
estimation with no stringent modeling assumptions; (ii) a black-box UQ method
for video models (termed S-QUBED), which leverages latent modeling to
rigorously decompose predictive uncertainty into its aleatoric and epistemic
components; and (iii) a UQ dataset to facilitate benchmarking calibration in
video models. By conditioning the generation task in the latent space, we
disentangle uncertainty arising due to vague task specifications from that
arising from lack of knowledge. Through extensive experiments on benchmark
video datasets, we demonstrate that S-QUBED computes calibrated total
uncertainty estimates that are negatively correlated with the task accuracy and
effectively computes the aleatoric and epistemic constituents.