An infinite-horizon perfect-information "centipede" game is studied. The unique subgame-perfect Nash equilibrium (SPNE) in pure strategies has each player choose, at each opportunity, to terminate the game. In contrast, mixed strategies can yield equilibrium cooperation described as follows: for...

We consider mixed populations (N=21) of genuine (humans) and artificial (robots) agents, repeatedly interacting in small groups whose composition is changed randomly from round to round. Our purpose is to study the spread of cooperative or non-cooperative behavior in the population over time by...

This paper studies the interaction of beliefs, payoff parameters, and the cooperation rate in the infinitely repeated prisoner's dilemma. We show formally that a player's belief about the probability of cooperation by their opponent moderates the effect of changes in the payoff parameters on...

Case studies of cartels and recent theory suggest that repeated communication is key for stable cooperation in environments where signals about others' actions are noisy. However, empirically the exact role of communication is not well understood. We study cooperation under different monitoring...

Conditional cooperation is usually investigated in experiments where the choices of others are known. In many circumstances, however, there is uncertainty about others’ cooperativeness. Using a novel experimental protocol, we manipulate the perceived likelihood of cooperation in a Prisoner's...

Reciprocal cooperation can be studied in the Centipede game, in which two players alternate in choosing between a cooperative GO move and a non-cooperative STOP move. GO sustains the interaction and increases the player pair's total payoff while incurring a small personal cost; STOP terminates...