We investigate the development of cooperative behavior in networks over time. In our controlled laboratory experiment, subjects can cooperate by sending costly messages that contain valuable information for the receiver or other subjects in the network. Any message sent can increase the chance that subjects find the information they are looking for and consequently their profit. We find that cooperation emerges spontaneously and remains stable over time. In an additional treatment, we provide a non-binding suggestion about who to contact at the beginning of the experiment. We find that subjects partially follow our recommendation, and this increases their own and others’ profit. Despite the removal of suggestions, subjects build long-lasting relationships with the suggested contacts.

我们研究网络中合作行为随时间的发展。在我们的受控实验室实验中，受试者可以通过发送昂贵的消息来进行合作，这些消息包含对接收者或网络中其他受试者有价值的信息。发送的任何消息都可以增加受试者找到他们正在寻找的信息的机会，从而增加他们的利润。我们发现合作是自发产生的，并且随着时间的推移保持稳定。在额外的治疗中，我们提供了关于在实验开始时联系谁的非约束性建议。我们发现受试者部分遵循我们的建议，这增加了他们自己和他人的利润。尽管删除了建议，受试者仍与建议的联系人建立了持久的关系。