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Evolution of Conditional Cooperation 1.1.0

Human societies are unique in the level of cooperation among non-kin. Evolutionary models explaining this behavior typically assume pure strategies of cooperation and defection. Behavioral experiments, however, demonstrate that humans are typically conditional co-operators who have other-regarding preferences. Building on existing models on the evolution of cooperation and costly punishment, we use a utilitarian formulation of agent decision making to explore conditions that support the emergence of cooperative behavior. Our results indicate that cooperation levels are significantly lower for larger groups in contrast to the original pure strategy model. Here, defection behavior not only diminishes the public good, but also affects the expectations of group members leading conditional co-operators to change their strategies. Hence defection has a more damaging effect when decisions are based on expectations and not only pure strategies.
This is a companion discussion topic for the original entry at

Dear Marc,

this model seems very interesting. I wanted to check it out and noticed that it was programmed to run on an old Netlogo version, this is why it is not running at the current version 6.2. Is there an updated model?


As the documentation says, it is implemented in NetLogo 5.0.3. Older versions of NetLogo are available at Download NetLogo

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