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Robust Estimation of Effective Diffusions from Multiscale Data

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 نشر من قبل Giacomo Garegnani
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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We present a methodology based on filtered data and moving averages for estimating robustly effective dynamics from observations of multiscale systems. We show in a semi-parametric framework of the Langevin type that the method we propose is asymptotically unbiased with respect to homogenization theory. Moreover, we demonstrate with a series of numerical experiments that the method we propose here outperforms traditional techniques for extracting coarse-grained dynamics from data, such as subsampling, in terms of bias and of robustness.



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