Emergence and suppression of cooperation by action visibility in transparent games
Fig 6
Frequencies of strategies that survived for more than 1000 generations after they emerged in the iterated Prisoner’s Dilemma population as function of reward R for mutual cooperation.
Data exemplified for psee = 0.3 and for psee = 0.5. Values of T, S and P are the same as in Fig 2, values of R are in range (S + T)/2 < R < T that defines the Prisoner’s Dilemma payoff. The frequencies were computed over 109 generations in 40 runs. We describe as “other cooperative” all strategies having a pattern (1*1*;1***;****) or (1**1;1***;****) but different from WSLS, TFT and FbF. While for psee = 0.3 population for low R mainly consists of defectors, for psee = 0.5 L-F provides an alternative to defection. For R ≥ 3.2 mutual cooperation becomes much more beneficial, which allows cooperative strategies to prevail for all transparency levels. Yet higher transparency reduces cooperation for all values of R. Note that the higher R is the less specific the cooperative strategies are. Indeed, for high R cooperation is much more effective than other types of behaviour, which makes all cooperative strategies (including even unconditional cooperation) evolutionary successful (we refer to [24] for a similar result in the case of sequential iPD).