Efficiency may improve when defectors exist
Takako Fujiwara-Greve (),
Masahiro Okuno-Fujiwara () and
Nobue Suzuki ()
Economic Theory, 2015, vol. 60, issue 3, 423-460
In repeated Prisoner’s Dilemma, the C-trigger strategy played by all players is well known to achieve symmetric efficiency when players are sufficiently patient. By contrast, if players are free to quit a repeated Prisoner’s Dilemma without information flow to new partners, cooperation from the outset of new partnerships cannot be a part of any symmetric equilibrium. Fujiwara-Greve and Okuno-Fujiwara (Rev Econ Stud 76:993–1021, 2009 ) showed that symmetric trust-building strategies can constitute an equilibrium for sufficiently long initial (D, D) (trust-building) periods. However, trust-building periods create social loss of payoffs, and there is a possibility that an asymmetric equilibrium with some players cooperating immediately, while others defect, may be more efficient. We show that there is a “fundamentally asymmetric” locally stable Nash equilibrium consisting of the most cooperative strategy (C-trigger with ending the partnership when betrayed) and the most noncooperative strategy, which plays D and ends the partnership immediately. When the deviation gain is relatively small, the fundamentally asymmetric equilibrium is neutrally stable against equilibrium entrants within trust-building strategies and is more efficient than any Nash equilibrium consisting of non-degenerate trust-building strategies. Our result indicates that behavioral diversity can be stable and beneficial for the society, even if players are free to escape from personalized punishments. Copyright Springer-Verlag Berlin Heidelberg 2015
Keywords: Efficiency; Diversity; Voluntary separation; Prisoner’s Dilemma; Endogenous partnerships; C73 (search for similar items in EconPapers)
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1) Track citations by RSS feed
Downloads: (external link)
Access to full text is restricted to subscribers.
Working Paper: Efficiency may Improve when Defectors Exist (2013)
This item may be available elsewhere in EconPapers: Search for items with the same title.
Export reference: BibTeX
RIS (EndNote, ProCite, RefMan)
Persistent link: https://EconPapers.repec.org/RePEc:spr:joecth:v:60:y:2015:i:3:p:423-460
Ordering information: This journal article can be ordered from
http://www.springer. ... eory/journal/199/PS2
Access Statistics for this article
Economic Theory is currently edited by Nichoals Yanneils
More articles in Economic Theory from Springer, Society for the Advancement of Economic Theory (SAET) Contact information at EDIRC.
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().