Memory- n strategies of direct reciprocity
Abstract
Direct reciprocity is one of the fundamental mechanisms for cooperation. It is based on the idea that individuals are more likely to cooperate if they can expect their beneficiaries to remember and to return their cooperative acts in future. Previous computational models, however, often had to restrict the number of past rounds subjects can memorize. Herein we suggest an alternative approach. We propose general properties that robust cooperative strategies ought to have. Then we characterize all memory- n strategies that meet these properties, and we show that such strategies naturally emerge across different evolutionary scenarios. Our results are applicable to general social dilemmas of arbitrary size. For some dilemmas, longer memory is all it takes for cooperation to evolve.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 18, 2017
- Source ID
- 10.1073/pnas.1621239114
Entities
People
- Christian Hilbe
- Krishnendu Chatterjee
- Luis A. Martinez-vaquero
- Martin A. Nowak
Organizations
- Austrian Science Fund
- Harvard University
- Institute of Cognitive Sciences and Technologies
- Institute of Science and Technology Austria
- Office of Naval Research