We use the Hendricks and Kovenock (RAND J Econ 20(2):164–182, 1989 ) framework to study the consumer problem under an informational externality. The informational externality arises when each consumer of a social network is endowed with private information regarding the quality of a good. In such situations, the past purchasing decisions of the consumers are informative and, thus, are used as partially revealing signals of private information. Asymmetric information and the observability of actions render the consumer problem dynamic and strategic because the purchasing decision of a consumer affects the other consumers’ future payoffs through the learning process. We show that there exists a unique symmetric Bayesian–Nash equilibrium. The informational externality increases the likelihood for a consumer to refrain from purchasing the good immediately to make a more informed decision in the future.

中文翻译：

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信息外部性下的消费者问题

我们使用Hendricks和Kovenock（RAND J Econ 20（2）：164-182，1989）框架来研究信息外部性下的消费者问题。当社交网络的每个消费者都获得有关商品质量的私人信息时，就会出现信息外部性。在这样的情况下，消费者过去的购买决定是有益的，因此被用作私人信息的部分揭示信号。信息的不对称和行为的可观察性使消费者的问题具有动态性和战略性，因为一个消费者的购买决策会通过学习过程影响其他消费者的未来收益。我们表明存在一个独特的对称贝叶斯-纳什均衡。