In the literature of voluntarily repeated Prisoner's Dilemma, the focus is on how long-term cooperation is established, when newly matched partners cannot know the past actions of each other. In this paper we investigate how non-cooperative and cooperative players co-exist. In many incomplete...

We show that it is evolutionarily stable that some players behave cooperatively while others act myopically, after any length of "trust-building" phase, where the partners do not cooperate but keep the partnership, in the Voluntarily Separable Repeated Prisoner's Dilemma (Fujiwara-Greve and...

Voluntarily Separable Repeated Prisoner's Dilemma (Fujiwara-Greve and Okuno-Fujiwara, 2009) has many kinds of equilibria. Focusing on monomorphic and bimorphic equilibria, we show that a bimorphic equilibrium consisting of cooperators and defectors is most efficient, under a mild payoff...

Ordinary repeated games do not apply to real societies where one can cheat and escape from partners. We formulate a model of endogenous relationships that a player can unilaterally end and start with a randomly assigned new partner with no information flow. Focusing on two-person, two-action...

In the literature of voluntarily repeated Prisoner's Dilemma type games with no information flow, the focus is on how long-term cooperation is established. In this paper we investigate how non-cooperative and cooperative players co-exist. In many incomplete information versions of a similar...