Source-linked AI summary
Evolution of cooperation on scale-free networks subject to error and attack
Matjaz Perc
TL;DR
The paper examines how random errors and targeted attacks affect cooperation in prisoner’s dilemma and snowdrift games on scale-free networks. Simulations show cooperation is robust to random deletion but declines rapidly under attacks on high-degree vertices, especially when defection is strongly tempting, as network heterogeneity falls.
Problem
The study asks whether cooperation on scale-free networks has attack and error tolerance laws resembling those observed for information propagation and epidemic spread.
Method
The authors simulate prisoner’s dilemma and snowdrift games on Barabási–Albert scale-free networks, comparing random vertex deletion with removal of the highest-degree vertices and measuring degree heterogeneity.
Results
Cooperation is extremely robust against random deletion but declines rapidly under targeted attack, with attack tolerance lowest at high temptation to defect; at b = 2, 87% of cooperators are replaced at Λ = 0.03.
Takeaways & Limitations
Targeted removal of high-degree vertices reduces network heterogeneity and thereby impairs cooperation, linking cooperation tolerance to network-fragmentation thresholds and prior results on viral spread and information propagation.
Abstract
from arXiv · showhide
We study the evolution of cooperation in the prisoner's dilemma and the snowdrift game on scale-free networks that are subjected to intentional and random removal of vertices. We show that, irrespective of the game type, cooperation on scale-free networks is extremely robust against random deletion of vertices, but declines fast if vertices with the maximal degree are targeted. In particular, attack tolerance is lowest if the temptation to defect is largest, whereby a small fraction of removed vertices suffices to decimate cooperators. The decline of cooperation can be directly linked to the decrease of heterogeneity of scale-free networks that sets in due to the removal of high degree vertices. We conclude that the evolution of cooperation is characterized by similar attack and error tolerance as was previously reported for information readiness and spread of viruses on scale-free networks.