{"title":"Mixed Strategies in the Indefinitely Repeated Prisoner's Dilemma","authors":"Julian Romero, Yaroslav Rosokha","doi":"10.3982/ECTA17482","DOIUrl":null,"url":null,"abstract":"<div>\n <p>Identifying the strategies that are played is critical to understanding behavior in repeated games. This process is difficult because only choices (not strategies) are observable. Recently, a debate has emerged regarding whether subjects play mixed strategies in the indefinitely repeated prisoner's dilemma. We use an experimental approach to elicit mixed strategies from human subjects, thereby providing direct empirical evidence. We find that a majority of subjects use mixed strategies. However, the data also suggest subjects' strategies are becoming less mixed over time, and move toward three focal pure strategies: Tit For Tat, Grim Trigger, and Always Defect. We use the elicited strategies to provide an empirically-relevant foundation for analyzing commonly used mixture model estimation procedures.</p>\n </div>","PeriodicalId":50556,"journal":{"name":"Econometrica","volume":null,"pages":null},"PeriodicalIF":6.6000,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.3982/ECTA17482","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Econometrica","FirstCategoryId":"96","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.3982/ECTA17482","RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ECONOMICS","Score":null,"Total":0}
引用次数: 0
Abstract
Identifying the strategies that are played is critical to understanding behavior in repeated games. This process is difficult because only choices (not strategies) are observable. Recently, a debate has emerged regarding whether subjects play mixed strategies in the indefinitely repeated prisoner's dilemma. We use an experimental approach to elicit mixed strategies from human subjects, thereby providing direct empirical evidence. We find that a majority of subjects use mixed strategies. However, the data also suggest subjects' strategies are becoming less mixed over time, and move toward three focal pure strategies: Tit For Tat, Grim Trigger, and Always Defect. We use the elicited strategies to provide an empirically-relevant foundation for analyzing commonly used mixture model estimation procedures.
要理解重复博弈中的行为,识别所采取的策略至关重要。这一过程非常困难,因为只有选择(而非策略)是可观察的。最近,关于受试者在无限重复的囚徒困境中是否会采取混合策略的争论出现了。我们使用实验方法从人类受试者那里诱发混合策略,从而提供直接的实证证据。我们发现,大多数被试使用混合策略。不过,数据也表明,随着时间的推移,受试者的混合策略越来越少,而趋向于三种焦点纯策略:以牙还牙(Tit For Tat)、严峻触发(Grim Trigger)和始终缺陷(Always Defect)。我们利用所激发的策略为分析常用的混合模型估计程序提供了一个与经验相关的基础。
期刊介绍:
Econometrica publishes original articles in all branches of economics - theoretical and empirical, abstract and applied, providing wide-ranging coverage across the subject area. It promotes studies that aim at the unification of the theoretical-quantitative and the empirical-quantitative approach to economic problems and that are penetrated by constructive and rigorous thinking. It explores a unique range of topics each year - from the frontier of theoretical developments in many new and important areas, to research on current and applied economic problems, to methodologically innovative, theoretical and applied studies in econometrics.
Econometrica maintains a long tradition that submitted articles are refereed carefully and that detailed and thoughtful referee reports are provided to the author as an aid to scientific research, thus ensuring the high calibre of papers found in Econometrica. An international board of editors, together with the referees it has selected, has succeeded in substantially reducing editorial turnaround time, thereby encouraging submissions of the highest quality.
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