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Title: Long ties accelerate noisy threshold-based contagions
In widely used models of biological contagion, interventions that randomly rewire edges (generally making them 'longer') accelerate spread. However, recent work has argued that highly clustered, rather than random, networks facilitate the spread of threshold-based contagions, such as those motivated by myopic best response for adoption of new innovations, norms and products in games of strategic complement. Here we show that minor modifications to this model reverse this result, thereby harmonizing qualitative facts about how network structure affects contagion. We analyse the rate of spread over circular lattices with rewired edges and show that having a small probability of adoption below the threshold probability is enough to ensure that random rewiring accelerates the spread of a noisy threshold-based contagion. This conclusion is verified in simulations of empirical networks and remains valid with partial but frequent enough rewiring and when adoption decisions are reversible but infrequently so, as well as in high-dimensional lattice structures.  more » « less
Award ID(s):
2318844
PAR ID:
10526758
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Nature
Date Published:
Journal Name:
Nature Human Behaviour
Volume:
8
Issue:
6
ISSN:
2397-3374
Page Range / eLocation ID:
1057 to 1064
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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