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arXiv · 2508.04884

The Cosine Schedule is Fisher-Rao-Optimal for Masked Discrete Diffusion Models

Leo Zhang·Saifuddin Syed
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Abstract

In this work, we study the problem of choosing the discretisation schedule for sampling from masked discrete diffusion models in terms of the information geometry of the induced probability path. Specifically, we show that the optimal schedule under the Fisher-Rao geometry recovers the popularly-used cosine schedule.

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Leo Zhang, Saifuddin Syed. 2025-10-05. The Cosine Schedule is Fisher-Rao-Optimal for Masked Discrete Diffusion Models. https://arxiv.org/abs/2508.04884

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