Refereed journal article or data article (A1)

Independent component analysis for multivariate functional data

List of AuthorsVirta Joni, Li Bing, Oja Hannu, Nordhausen Klaus

PublisherElsevier BV

Publication year2020

JournalJournal of Multivariate Analysis

Volume number176

Number of pages19




Self-archived copy’s web address


We extend two methods of independent component analysis, fourth order blind identification and joint approximate diagonalization of eigen-matrices, to vector-valued functional data. Multivariate functional data occur naturally and frequently in modern applications, and extending independent component analysis to this setting allows us to distill important information from this type of data, going a step further than the functional principal component analysis. To allow the inversion of the covariance operator we make the assumption that the dependency between the component functions lies in a finite-dimensional subspace. In this subspace we define fourth cross-cumulant operators and use them to construct the two novel, Fisher consistent methods for solving the independent component problem for vector-valued functions. Both simulations and an application on a hand gesture data set show the usefulness and advantages of the proposed methods over functional principal component analysis.

Last updated on 2021-24-06 at 10:27