Complexity Demonstrated

My first step in developing a research topic is to recreate one of the classic works of the field. In this case, I need to reproduce the results of an agent-based model of agents playing prisoners dilemma with one another on a two-dimensional grid. The article by Nowak and May was published in 1992:

Nowak, Martin A., and Robert M. May. "Evolutionary games and spatial chaos". Nature 359 (29 October 1992), p. 826-829.

I have successfully re-done their model in NetLogo. Compare my image of interlaced networks of defectors with their figure 1a.

This is the result of setting b = 1.799. The red regions are those agents who chose to defect. Blue represents those agents choosing to cooperate (with other agents), and the green and yellow patches are those agents that are switching sides every turn.

In 92 this was an interesting game theory agent-based model. But, today we only need to change "defect" to "support coaltion" and "cooperate" to "join insurgency" and we have an interesting model of the game theory of insurgency. If we change the payoff for 'defecting', we get very different outcomes. This illustration was taken just before one of those 'tipping points'. Increasing the reward to b = 1.800 will send the model into complete complex behavior. It won't be in chaos -- there will still be patches and strutuctures -- but it certainly won't be stable, either.