Diffusion in Networks and the Unexpected Virtue of Burstiness

TL;DR

This paper investigates how heterogeneity in activity patterns among individuals affects diffusion in networks, revealing that a mix of bursty and non-Poisson activity can enhance diffusion rather than hinder it.

Contribution

It demonstrates that heterogeneous activity patterns, including burstiness, can improve diffusion, challenging previous assumptions that bursty behavior always impedes spreading.

Findings

Heterogeneous activity patterns can significantly enhance diffusion.

Burstiness does not always hinder diffusion; it can be beneficial.

Optimal diffusion involves a mix of bursty and regular activity patterns.

Abstract

Whether an idea, information, infection, or innovation diffuses throughout a society depends not only on the structure of the network of interactions, but also on the timing of those interactions. Recent studies have shown that diffusion can fail on a network in which people are only active in "bursts", active for a while and then silent for a while, but diffusion could succeed on the same network if people were active in a more random Poisson manner. Those studies generally consider models in which nodes are active according to the same random timing process and then ask which timing is optimal. In reality, people differ widely in their activity patterns -- some are bursty and others are not. Here we show that, if people differ in their activity patterns, bursty behavior does not always hurt the diffusion, and in fact having some (but not all) of the population be bursty significantly helps diffusion. We prove that maximizing diffusion requires heterogeneous activity patterns across agents, and the overall maximizing pattern of agents' activity times does not involve any Poisson behavior.