Information Cascades and the Collapse of Cooperation

Guoli Yang,Matteo Cavaliere,Gaoxi Xiao,William Waites,Attila Csikász-Nagy

doi:10.1038/s41598-020-64800-z

Abstract

In various types of structured communities newcomers choose their interaction partners by selecting a role-model and copying their social networks. Participants in these networks may be cooperators who contribute to the prosperity of the community, or cheaters who do not and simply exploit the cooperators. For newcomers it is beneficial to interact with cooperators but detrimental to interact with cheaters. However, cheaters and cooperators usually cannot be identified unambiguously and newcomers’ decisions are often based on a combination of private and public information. We use evolutionary game theory and dynamical networks to demonstrate how the specificity and sensitivity of those decisions can dramatically affect the resilience of cooperation in the community. We show that promiscuous decisions (high sensitivity, low specificity) are advantageous for cooperation when the strength of competition is weak; however, if competition is strong then the best decisions for cooperation are risk-adverse (low sensitivity, high specificity). Opportune decisions based on private and public information can still support cooperation but suffer of the presence of information cascades that damage cooperation, especially in the case of strong competition. Our research sheds light on the way the interplay of specificity and sensitivity in individual decision-making affects the resilience of cooperation in dynamical structured communities.

Highlights

Cooperation is widespread in the real world and can be observed at different scales of biological organization, ranging from genes to multi-cellular organisms and socio-technological systems[1,2,3,4]
In this paper we use evolutionary game theory to study a model of dynamical networks to understand how attachment choices cascade down the generations and lead, or not, to a collapse of cooperation
We use the degree of a node for this public information, reasoning that if it is very popular, if more previous newcomers have connected to such node, following the crowd might be a good idea

Summary

Introduction

Cooperation is widespread in the real world and can be observed at different scales of biological organization, ranging from genes to multi-cellular organisms and socio-technological systems[1,2,3,4]. For stronger selection (e.g., δ = 0.1, Fig. 4 right panel) the detrimental effects for cooperation of mixed connections (facilitated when τ is large) are larger: the chances that a cheater connected to cooperators is selected as role-model (and imitated by future newcomers) are larger as δ increases.

Results

Conclusion