Wednesday, September 16, 2009

ETH - Chair of Sociology, in particular of Modeling and Simulation - Videos & Simulations

ETH - Chair of Sociology, in particular of Modeling and Simulation - Videos & Simulations

The outbreak of cooperation among success-driven individuals under noisy conditions

This is the supplementary webpage to the publication on The Outbreak of Cooperation in PNAS.

pnas_cover
Description of cover figure: Illustration of self-organized pattern formation in migration games. The snapshot, taken after 200 time steps, shows the outcome of the spatial interaction of mobile individuals, who strategically interact with their four nearest neighbors and copy the strategy of their most successful neighbor. The simulation assumes that individuals earn no payoff, if they meet individuals who use the same strategy, while their outcome is positive, if interacting with individuals using another strategy. Strategy 1 is represented by blue disks, strategy 2 by red disks. A change to strategy 2 in the last time step is indicated in green, a change to strategy 2 by yellow. White spaces are empty. Individuals perform success-driven migration, i.e. they move to empty locations with a higher expected payoff. The maximum migration distance in one time step was assumed to be 5. Starting with uniformly distributed strategies, one observes an agglomeration of individuals, and individuals with different strategies mix. This is to be distinguished from the migratory dynamics in other spatial games, which lead to segregation patterns, for example, as studied by Nobel prize winner Thomas Schelling. For animated videos see http://www.soms.ethz.ch/migrationgames.