Evolving networks for social optima in the “weakest link game”



Previous models have applied evolving networks based on node-level “copy and rewire” rules to simple two player games (e.g. the Prisoner’s Dilemma). It was found that such models tended to evolve toward socially optimal behavior. Here we apply a similar technique to a more tricky co-ordination game (the weakest link game) requiring interactions from several players (nodes) that may play several strategies. We define a variant of the game with several equilibria—each offering increasing social benefit. We found that the evolving network functions to select and spread more optimal equilibria while resisting invasion by lower ones. Hence the network acts as a kind of “social ratchet” selecting for increasing social benefit. Such networks have applications in peer-to-peer computing and may have implications for understanding social systems.


Coordination game Weakest link game Potential game Pareto-optimality P2P strategic interaction Game theory Equilibrium selection Evolution of cooperation 


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© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Dept. of Computer ScienceThe University of BolognaBolognaItaly

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