Corten Rense, Rosenkranz Stephanie, Buskens Vincent, Cook Karen S
Department of Sociology, Utrecht University, Utrecht, The Netherlands.
Utrecht School of Economics, Utrecht University, Utrecht, The Netherlands.
PLoS One. 2016 Jul 1;11(7):e0155703. doi: 10.1371/journal.pone.0155703. eCollection 2016.
Despite the popularity of the notion that social cohesion in the form of dense social networks promotes cooperation in Prisoner's Dilemmas through reputation, very little experimental evidence for this claim exists. We address this issue by testing hypotheses from one of the few rigorous game-theoretic models on this topic, the Raub & Weesie model, in two incentivized lab experiments. In the experiments, 156 subjects played repeated two-person PDs in groups of six. In the "atomized interactions" condition, subjects were only informed about the outcomes of their own interactions, while in the "embedded" condition, subjects were informed about the outcomes of all interactions in their group, allowing for reputation effects. The design of the experiments followed the specification of the RW model as closely as possible. For those aspects of the model that had to be modified to allow practical implementation in an experiment, we present additional analyses that show that these modifications do not affect the predictions. Contrary to expectations, we do not find that cooperation is higher in the embedded condition than in the atomized interaction. Instead, our results are consistent with an interpretation of the RW model that includes random noise, or with learning models of cooperation in networks.
尽管有一种观点很流行，即密集社交网络形式的社会凝聚力通过声誉促进囚徒困境中的合作，但几乎没有实验证据支持这一说法。我们通过在两个有激励措施的实验室实验中检验关于这一主题的少数严格博弈论模型之一（劳布和韦西模型）的假设，来解决这个问题。在实验中，156名受试者以六人一组的形式进行重复的两人囚徒困境博弈。在“原子化互动”条件下，受试者只被告知他们自己互动的结果，而在“嵌入”条件下，受试者被告知他们所在组所有互动的结果，从而产生声誉效应。实验设计尽可能遵循RW模型的规范。对于模型中为了在实验中实际实施而必须修改的那些方面，我们进行了额外的分析，结果表明这些修改不会影响预测。与预期相反，我们没有发现嵌入条件下的合作比原子化互动中的合作更高。相反，我们的结果与包含随机噪声的RW模型解释一致，或者与网络中的合作学习模型一致。
