From brain to earth and climate systems: Small-world interaction networks or not?

TL;DR

This paper examines whether small-world network properties observed in spatially extended systems are genuine or artifacts of sampling and analysis methods, highlighting potential misinterpretations in neuroscience, geophysics, and meteorology.

Contribution

It reveals that small-world topologies may arise from sampling and analysis artifacts rather than true network structures in various scientific fields.

Findings

Sampling can produce false indications of small-world topology.

Common analysis methods may misinterpret spatial sampling as network features.

Caution is needed when inferring network properties from spatial data.

Abstract

We consider recent reports on small-world topologies of interaction networks derived from the dynamics of spatially extended systems that are investigated in diverse scientific fields such as neurosciences, geophysics, or meteorology. With numerical simulations that mimic typical experimental situations we have identified an important constraint when characterizing such networks: indications of a small-world topology can be expected solely due to the spatial sampling of the system along with commonly used time series analysis based approaches to network characterization.