Agents with Heterogeneous Strategies Interacting in a Spatial IPD

We use a spatial iterated Prisoner's Dilemma game (IPD) to investigate the spatial-temporal evolution of heterogeneity in agents' strategies. In our model, N agents are spatially distributed on a lattice and each agent is assumed to interact with her 4 local neighbors a number of n g times during each generation. If the agent has a one-step memory for the last action of each individual neighbor, this results in a total of eight different strategies for the game. After each generation, the agent will be replaced by an offspring that adopts the strategy of her most successful neighbor.