Seeking Escape: The Use of Escape Clauses in International Trade Agreements
In: International studies quarterly: the journal of the International Studies Association, Band 53, Heft 2, S. 349-368
ISSN: 1468-2478
In: International studies quarterly: the journal of the International Studies Association, Band 53, Heft 2, S. 349-368
ISSN: 1468-2478
In: Journal transition studies review: JTSR, Band 16, Heft 2, S. 343-351
ISSN: 1614-4015
In: The journal of conflict resolution: journal of the Peace Science Society (International), Band 53, Heft 5, S. 774-793
ISSN: 0022-0027, 0731-4086
In: The journal of conflict resolution: journal of the Peace Science Society (International), Band 53, Heft 5, S. 774-793
ISSN: 1552-8766
The aim of this article is to distinguish between strategies in the Iterated Prisoner's Dilemma on the basis of their relative performance in a given population set. We first define a natural order on such strategies that disregards isolated disturbances, by using the limit of time-average payoffs. This order allows us to consider one strategy as strictly better than another in some population of strategies. We then determine a strategy σ to be ''robust,'' if in any population consisting of copies of two types of strategies, σ itself and some other strategy τ, the strategy σ is never worse than τ. We present a large class of such robust strategies. Strikingly, robustness can accommodate an arbitrary level of generosity, conditional on the strength of subsequent retaliation; and it does not require symmetric retaliation. Taken together, these findings allow us to design strategies that significantly lessen the problem of noise, without forsaking performance. Finally, we show that no strategy exhibits robustness in all population sets of three or more strategy types.