Abstract

Matrix factorization is a powerful data analysis tool. It has been used in multivariate time series analysis, leading to the decomposition of the series in a small set of latent factors. However, little is known on the statistical performances of matrix factorization for time series. In this paper, we extend the results known for matrix estimation in the i.i.d setting to time series. Moreover, we prove that when the series exhibit some additional structure like periodicity or smoothness, it is possible to improve on the classical rates of convergence.

Highlights

  • Matrix factorization is a very powerful tool in statistics and data analysis

  • There, matrix factorization is mainly a tool to estimate a coefficient matrix under a low-rank constraint

  • Nonnegative matrix factorization (NMF) was introduced by [35] as a tool to represent a huge number of objects as linear combinations of elements of “parts” of objects

Read more

Summary

Introduction

Matrix factorization is a very powerful tool in statistics and data analysis. It was used as early as in the 70’s in econometrics in reduced-rank regression [27, 22, 29]. The factorization provides a decomposition of each series in a dictionary which member that can be interpreted as latent factors used for example in state-space models, see e.g. Chapter 3 in [33] For this reasons, matrix factorization was used in multivariate time series analysis beyond econometrics: electricity consumptions. Our estimator can be tuned to take into account a possible periodicity or smoothness of the series This is done by rewriting W = V Λ where Λ is a τ × T matrix encoding the temporal structure, and τ T.

Setting of the problem and notation
Oracle inequalities
Model selection

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.