In the identification of nonlinear dynamical models it may happen that not only the system dynamics have to be modeled but also the noise has a dynamic character. We show how to adapt Least Squares Support Vector Machines (LSSVMs) to take advantage of a known or unknown noise model. We furthermore investigate a convex approximation based on overparametrization to estimate a linear auto regressive noise model jointly with a model for the nonlinear system. Considering a noise model can improve generalization performance. We discuss several properties of the proposed scheme on synthetic data sets and finally demonstrate its applicability on real world data.
Tillmann Falck, Johan A. K. Suykens, Bart De Moor