RT Journal Article T1 Estimating Lyapunov exponents on a noisy environment by global and local Jacobian indirect algorithms A1 Escot Mangas, Lorenzo A1 Sandubete Galán, Julio Emilio A2 Simos, Theodore E. AB Most of the existing methods and techniques for the detection of chaotic behaviour from empirical time series try to quantify the well-known sensitivity to initial conditions through the estimation of the so-called Lyapunov exponents corresponding to the data generating system, even if this system is unknown. Some of these methods are designed to operate in noise-free environments, such as those methods that directly quantify the separation rate of two initially close trajectories. As an alternative, this paper provides two nonlinear indirect regression methods for estimating the Lyapunov exponents on a noisy environment. We extend the global Jacobian method, by using local polynomial kernel regressions and local neural net kernel models. We apply such methods to several noise-contaminated time series coming from different data generating processes. The results show that in general, the Jacobian indirect methods provide better results than the traditional direct methods for both clean and noisy time series. Moreover, the local Jacobian indirect methods provide more robust and accurate fit than the global ones, with the methods using local networks obtaining more accurate results than those using local polynomials. PB Elsevier SN 0096-3003 YR 2023 FD 2023-01-01 LK https://hdl.handle.net/20.500.14352/99625 UL https://hdl.handle.net/20.500.14352/99625 LA eng NO Escot, L.; Sandubete, J.E., “Estimating Lyapunov exponents on a noisy environment by global and local Jacobian indirect algorithms”. J. Applied Mathematics and Computation, (0096-3003), vol 436, 1 January, 2023, 127498. NO Goverment of Spain NO Faculty of Statistical Studies NO Computing and Artificial Itelligence Lab - Camilo José Cela University NO Data Analysis in Social and Gender Studies and Equality Policies UCM Research Group (www.ucm.es/aedipi/) DS Docta Complutense RD 21 jul 2024