Preferential Exchange: Strengthening Connections in Complex Networks

TL;DR

This paper investigates the distribution of connection strengths in complex networks, especially email networks, proposing a feedback-based mechanism that explains the emergence of broad, power-law distributions across various types of networks.

Contribution

It introduces a simple, feedback-driven model for connection reinforcement that accounts for observed power-law distributions in network connection strengths.

Findings

Power-law distributions of connection strengths are common across different networks.

A feedback and reciprocity mechanism explains the formation and reinforcement of network links.

The proposed model has broad applicability beyond social networks.

Abstract

Many social, technological and biological interactions involve network relationships whose outcome intimately depends on the structure of the network and on the strengths of the connections. Yet, although much information is now available concerning the structure of many networks, the strengths are more difficult to measure. Here we show that, for one particular social network, notably the e-mail network, a suitable measure of the strength of the connections can be available. We also propose a simple mechanism, based on positive feedback and reciprocity, that can explain the observed behavior and that hints toward specific dynamics of formation and reinforcement of network connections. Network data from contexts different from social sciences indicate that power-law, and generally broad, distributions of the connection strength are ubiquitous, and the proposed mechanism has a wide range of applicability.