On Six Advances in Cooperation Theory

1. On Six Advances in Cooperation Theory By Robert Axelrod Presentation by Matthew Brumberg

2. What is Cooperation Theory Addresses the tension between divergent long and short run goals. Uses game theory like the Prisoner’s Dilemma to answer questions about cooperation.

3. Cooperation Theory’s Central Questions • “Under what conditions can cooperation emerge and be sustained among actors who are egoists?” • “What advice can be offered to a player in a given setting about the best strategy to use?” • “What advice can be offered to reformers who want to alter the very terms of the interaction so as to promote the emergence of cooperation?”

4. Adaptive Actors vs. Rational Agents • Limited knowledge. • Limited ability to process information. • Limited time to make decisions. • More likely to mimic. • More likely to use rules of thumb.

5. Deduction vs. Simulation • Deduction can use axioms to prove theorems. • Simulation can provide statistical significance through data analysis. • Simulation is most useful with complex non-linear interactions. • Simulation provides ‘histories’ where patterns can be discerned. • Often ‘emergent properties’ arise from simulation.

6. Timing of Choices by Abell and Reyneirs (2000) • The Assumptions: • An alternating Prisoner’s Dilemma. • A bilateral Prisoner’s Dilemma. • Conclusion: “Cooperation based on reciprocity can be sustained if and only if the payoff parameters and the shadow of future are favorable enough”. • Single resource game – a possibility for further research.

7. Hostages by Raub and Weesie (2000) • Two Players: Trustee and ‘Trustor’. • Conclusions: • Reduces incentive of trustee to abuse trust. • Reduces cost to trustor if abused. • Demonstrates trustees ‘good will’. • Need to examine differences between voluntary and coercive hostage taking.

8. Social Networks by Buskens and Weesie (2000) • Examines cooperation through reputations. • Each player informs every other player of there past experiences. • Conclusions: • More simulation is needed. • Cooperation is heavily dependent on who tells what to whom. • Favorable networks do favor cooperation.

9. Rational and Adaptive Agents by Hegselmann and Flache (2000) • Studies rational vs. adaptive agents differing conditions for cooperation. • Rational agents are “Grim Reeper and Tit for Tat” • Adaptive agents are ‘learning strategies’. • Conclusions: • Agents who adapt during a game fail to thrive. • Agents who evolve during generations may be more robust. • More work in the field is needed.

10. Envy byLehno (2000) • Studies envy in a ‘noisy environment’. • Moderate envy - will not get ahead in defections. • Conclusions: • Envy is feasible in the sense of demanding a ‘fair game’ - not being abused. • Try to better yourself, not yourself vs. another individual.

11. Exit by The Edk-Group (2000) • Uses the PD. • “…analyzes the effect of allowing players to exit from an unsatisfactory relationship.” • Studies adaptive strategies - least successful strategies convert randomly to more successful strategies. • Conclusions: • Most successful strategies exited on first defection. • Safe but weak strategies survive in certain adaptation rules. • Penalties to exit vary cooperation.