Flow matching achieves almost minimax optimal convergence
- URL: http://arxiv.org/abs/2405.20879v2
- Date: Thu, 10 Oct 2024 22:43:10 GMT
- Title: Flow matching achieves almost minimax optimal convergence
- Authors: Kenji Fukumizu, Taiji Suzuki, Noboru Isobe, Kazusato Oko, Masanori Koyama,
- Abstract summary: Flow matching (FM) has gained significant attention as a simulation-free generative model.
This paper discusses the convergence properties of FM for large sample size under the $p$-Wasserstein distance.
We establish that FM can achieve an almost minimax optimal convergence rate for $1 leq p leq 2$, presenting the first theoretical evidence that FM can reach convergence rates comparable to those of diffusion models.
- Score: 50.38891696297888
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- Abstract: Flow matching (FM) has gained significant attention as a simulation-free generative model. Unlike diffusion models, which are based on stochastic differential equations, FM employs a simpler approach by solving an ordinary differential equation with an initial condition from a normal distribution, thus streamlining the sample generation process. This paper discusses the convergence properties of FM for large sample size under the $p$-Wasserstein distance, a measure of distributional discrepancy. We establish that FM can achieve an almost minimax optimal convergence rate for $1 \leq p \leq 2$, presenting the first theoretical evidence that FM can reach convergence rates comparable to those of diffusion models. Our analysis extends existing frameworks by examining a broader class of mean and variance functions for the vector fields and identifies specific conditions necessary to attain almost optimal rates.
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