Necrotic Behavioral Control of Agent Behavior in the Iterated Prisoner's Dilemma

As the Covid-19 pandemic of 2020 illustrates, controlling the behavior of social agents is a difficult problem. This study examines the potential for an immune-inspired technique called necrosis to steer the behavior of agent populations that are evolving to play the iterated version of the game prisoner's dilemma. A key factor in this is detection of behavioral types. The use of a previously developed technique for fingerprinting the behavior of game playing agents, even complex ones, permits the modelling of control strategies with necrotic behavioral control (NBC). NBC consists of reducing the fitness of agents engaging in an unacceptable behavior. The impact of applying necrosis to a number of agent behaviors is investigated. The strategies always-defect, always-cooperate, and tit-for-two-tats are used as the foci for behavior control by zeroing out the fitness of agents whose behavior is similar to those agents. Our experiments demonstrate that NBC changes the distribution of prisoner's dilemma strategies that arise both when the focal strategy is changed and when the similarity radius used to zero out agent fitness is changed. Filtration focused on the strategy tit-for-two-tats has the largest impact on the evolution of prisoner's dilemma strategies while always cooperate is found to have the least.