Friendship is commonly assumed to reduce strategic uncertainty and enhance tacit coordination. However, this assumption has never been tested across two opposite poles of coordination involving either strategic complementarity or substitutability. We had participants interact with friends or strangers in two classic coordination games: the stag-hunt game, which exhibits strategic complementarity and may foster “cooperation”, and the entry game, which exhibits strategic substitutability and may foster “competition”. Both games capture a frequent trade-off between a potentially high paying but uncertain option and a low paying but safe alternative. We find that, relative to strangers, friends are more likely to choose options involving uncertainty in stag-hunt games, but the opposite is true in entry games. Furthermore, in stag-hunt games, friends “tremble” less between options, coordinate better and earn more, but these advantages are largely decreased or lost in entry games. We further investigate how these effects are modulated by risk attitudes, friendship qualities, and interpersonal similarities.

中文翻译：

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友谊对合作与竞争协调的不同影响

通常认为友谊可以减少战略不确定性并加强默契协调。但是，这一假设从未在涉及战略互补性或可替代性的两个相对协调极点进行过检验。我们在两个经典的协调游戏中让参与者与朋友或陌生人互动：展示战略互补性并可能促进“合作”的追逐游戏，以及表现出战略可替代性并可能促进“竞争”的入门游戏。两种游戏都经常在潜在的高薪但不确定的选择与低薪但安全的选择之间进行权衡。我们发现，相对于陌生人，朋友更有可能在雄鹿狩猎游戏中选择涉及不确定性的选项，但在入门游戏中则相反。此外，在雄鹿狩猎游戏中，朋友在选项之间“颤抖”的次数减少了，协调更好，赚了更多，但是这些优点在入门游戏中被大大削弱或丧失了。我们将进一步研究如何通过风险态度，友谊素质和人际相似性来调节这些影响。