Community Dynamics Group, Department of Evolutionary Ecology, Max-Planck-Institute for Evolutionary Biology, August-Thienemann-Strasse 2, 24306, Plön, Germany.
University of Konstanz, Mainaustraße 252, 78464, Konstanz, Germany.
Nat Commun. 2019 Feb 15;10(1):783. doi: 10.1038/s41467-019-08671-7.
Cooperative strategies are predicted for repeated social interactions. The recently described Zero Determinant (ZD) strategies enforce the partner's cooperation because the 'generous' ZD players help their cooperative partners while 'extortionate' ZD players exploit their partners' cooperation. Partners may accede to extortion because it pays them to do so, but the partner can sabotage his own and his extortioner's score by defecting to discipline the extortioner. Thus, extortion is predicted to turn into generous and disappear. Here, we show with human volunteers that an additional monetary incentive (bonus) paid to the finally competitively superior player maintains extortion. Unexpectedly, extortioners refused to become disciplined, thus forcing partners to accede. Occasional opposition reduced the extortioners' gain so that using extortion paid off only because of the bonus. With no bonus incentive, players used the generous ZD strategy. Our findings suggest that extortion strategies can prevail when higher competitiveness is rewarded with extra gain.
合作策略是针对重复的社会互动而预测的。最近描述的零决定（ZD）策略强制合作伙伴合作，因为“慷慨”的 ZD 玩家在帮助他们的合作伙伴，而“剥削”的 ZD 玩家则利用他们的合作伙伴的合作。合作伙伴可能会屈服于剥削，因为这样做对他们有利，但合作伙伴可以通过背叛来破坏自己和剥削者的分数，从而惩罚剥削者。因此，预计剥削会转变为慷慨并消失。在这里，我们用人作为志愿者证明，额外的金钱奖励（奖金）支付给最终具有竞争优势的玩家可以维持剥削。出乎意料的是，剥削者拒绝接受纪律处分，从而迫使合作伙伴屈服。偶尔的反对减少了剥削者的收益，因此只有因为奖金，使用剥削才会有回报。没有奖金激励，玩家就会使用慷慨的 ZD 策略。我们的发现表明，当更高的竞争力得到额外收益的奖励时，剥削策略可能会占上风。
