title: Intrinsic multi-scale analysis: a multi-variate empirical mode decomposition framework.
abstract: A novel multi-scale approach for quantifying both inter- and intra-component dependence of a complex system is introduced. This is achieved using empirical mode decomposition (EMD), which, unlike conventional scale-estimation methods, obtains a set of scales reflecting the underlying oscillations at the intrinsic scale level. This enables the data-driven operation of several standard data-association measures (intrinsic correlation, intrinsic sample entropy (SE), intrinsic phase synchrony) and, at the same time, preserves the physical meaning of the analysis. The utility of multi-variate extensions of EMD is highlighted, both in terms of robust scale alignment between system components, a pre-requisite for inter-component measures, and in the estimation of feature relevance. We also illuminate that the properties of EMD scales can be used to decouple amplitude and phase information, a necessary step in order to accurately quantify signal dynamics through correlation and SE analysis which are otherwise not possible. Finally, the proposed multi-scale framework is applied to detect directionality, and higher order features such as coupling and regularity, in both synthetic and biological systems.
authors.affiliation: Department of Electrical and Electronic Engineering , Imperial College London , London SW7 2AZ, UK.
authors.forename: David
authors.initials: D
authors.lastname: Looney
authors.affiliation: Department of Electrical and Electronic Engineering , Imperial College London , London SW7 2AZ, UK.
authors.forename: Apit
authors.initials: A
authors.lastname: Hemakom
authors.affiliation: Department of Electrical and Electronic Engineering , Imperial College London , London SW7 2AZ, UK.
authors.forename: Danilo P
authors.initials: DP
authors.lastname: Mandic
keywords: correlation; empirical mode decomposition; multi-variate analysis; phase synchrony; sample entropy