arXiv Machine Learning By Jonas Arruda, Jan Hasenauer, Stefan T. Radev

Conditional Mean Flows: Few-Step Densities for Simulation-Based Inference

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Conditional Mean Flows introduce a new approach for simulation-based inference that replaces the costly numerical integration of traditional flow matching with few-step sampling and tractable density evaluation. By identifying conditional flow maps through a mean flow objective and using independent masking, the method allows direct estimation of marginal likelihoods. Experiments demonstrate that single-step conditional mean flow density evaluation achieves error comparable to 200-step flow matching while accelerating downstream MCMC sampling by roughly 200‑fold.

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