Time Series Analysis via Network Science: Concepts and Algorithms

TL;DR

This paper reviews methods that transform time series data into networks, providing a structured overview of concepts, algorithms, and their advantages and limitations to advance research in this emerging area.

Contribution

It offers a comprehensive, unified review of network-based time series analysis methods, highlighting their main characteristics and differences for both univariate and multivariate data.

Findings

Classifies mapping methods into visibility, transition, and proximity approaches.

Discusses single layer and multiple layer network techniques.

Identifies advantages and limitations of each methodology.

Abstract

There is nowadays a constant flux of data being generated and collected in all types of real world systems. These data sets are often indexed by time, space or both requiring appropriate approaches to analyze the data. In univariate settings, time series analysis is a mature and solid field. However, in multivariate contexts, time series analysis still presents many limitations. In order to address these issues, the last decade has brought approaches based on network science. These methods involve transforming an initial time series data set into one or more networks, which can be analyzed in depth to provide insight into the original time series. This review provides a comprehensive overview of existing mapping methods for transforming time series into networks for a wide audience of researchers and practitioners in machine learning, data mining and time series. Our main contribution is a structured review of existing methodologies, identifying their main characteristics and their differences. We describe the main conceptual approaches, provide authoritative references and give insight into their advantages and limitations in a unified notation and language. We first describe the case of univariate time series, which can be mapped to single layer networks, and we divide the current mappings based on the underlying concept: visibility, transition and proximity. We then proceed with multivariate time series discussing both single layer and multiple layer approaches. Although still very recent, this research area has much potential and with this survey we intend to pave the way for future research on the topic.