Intervention(s)
The aim of the experiment is to test the cooperative behavior of individuals in the infinitely repeated prisoners’ dilemma (IRPD) with reinforcement, i.e., cooperation has neutral feedback, positive feedback or negative feedback. In case of positive (negative) feedback, mutual cooperation in round t of the IRPD leads to an increase (decrease) of payoffs in the payoff matrix in round t + 1, compared to neutral feedback where payoffs in the payoff matrix stay constant during the entire game.
We differentiate between two cases: In the first round of the infinitely repeated prisoners’ dilemma, mutual cooperation is either a sub-game perfect equilibrium (SPE) or not.
We plan to run 5 main treatments:
• Neutral Feedback – Cooperation is a SPE and remains so
• Positive Feedback – Cooperation is a SPE and remains so
• Negative Feedback – Cooperation is a SPE but can stop being a SPE in the mid-term
• Neutral Feedback – Cooperation is not a SPE and can never become a SPE
• Positive Feedback – Cooperation is not a SPE but can become a SPE in the mid-term
We furthermore plan to run 4 sub-treatments, where mutual cooperation has short-term or long-term consequences (compared to mid-term consequences in the main treatments):
• Negative Feedback – Cooperation is a SPE but can stop being a SPE in the short-term
• Negative Feedback – Cooperation is a SPE but can stop being a SPE in the long-term
• Positive Feedback – Cooperation is not a SPE but can become a SPE in the short-term
• Positive Feedback – Cooperation is not a SPE but can become a SPE in the long-term
We finally plan to run 3 control treatments, where individuals play a finitely repeated prisoner’s dilemma (FRPD) instead of an IRPD (in the FRPD, players know the exact number of rounds of the prisoner’s dilemma):
• Negative Feedback (FRPD) – Cooperation is a SPE but can stop being a SPE in the mid-term
• Neutral Feedback (FRPD) – Cooperation is not a SPE and can never become a SPE
• Positive Feedback(FRPD) – Cooperation is not a SPE but can become a SPE in the mid-term