Repository: Freie Universität Berlin, Math Department

Estimation of the Koopman generator by Newton’s extrapolation

Sechi, Renata and Sikorski, Alexander and Weber, Marcus (2021) Estimation of the Koopman generator by Newton’s extrapolation. SIAM Multiscale Modeling & Simulation, 19 (2). pp. 758-774. ISSN print: 1540-3459; online: 1540-3467

Full text not available from this repository.

Official URL: https://doi.org/10.1137/20M1333006

Abstract

This article addresses the problem of estimating the Koopman generator of a Markov process. The direct computation of the infinitesimal generator is not easy because of the discretization of the state space, in particular because of the trade-off inherent in the choice of the best lag time to study the process. Short lag times implies a strong discretization of the state space and a consequent loss of Markovianity. Large lag times bypass events on fast timescales. We propose a method to approximate the generator with the computation of the Newton polynomial extrapolation. This technique is a multistep approach which uses as its input Koopman transfer operators evaluated for a series of lag times. Thus, the estimated infinitesimal generator combines information from different time resolutions and does not bias only fast- or slow-decaying dynamics. We show that the multi-scale Newton method can improve the estimation of the generator in comparison to the computation using finite difference or matrix logarithm methods. Read More: https://epubs.siam.org/doi/abs/10.1137/20M1333006?mobileUi=0

Item Type:Article
Subjects:Mathematical and Computer Sciences > Mathematics > Applied Mathematics
ID Code:2717
Deposited By: Monika Drueck
Deposited On:11 Feb 2022 14:30
Last Modified:11 Feb 2022 14:30

Repository Staff Only: item control page