The review systems of online platforms create a stream of online word-of-mouth that allows consumers to learn from others' purchasing experience. However, it is difficult for consumers to discern the authenticity of a review or the reviewer's level of experience with the product. Platforms can aid the authentication process by incorporating a verified purchase (VP) indication, or “badge” as is done on Amazon, in reviews where the consumer writing the review has verifiably purchased the focal product. A VP is a revealed preference for a product implying a utility-maximizing choice where the consumer writing the review has experience with the product. Combining an Amazon dataset on tablet computers with the theory of revealed preference in online reviews, we uncover a surprising new result: the proportion of VP reviews (a revealed preference) is associated with higher future sales, and the effect of the proportion of VP reviews on sales dominates the effect of the mean rating. This novel use of VP with revealed preference theory has implications for new research in the design of recommendation systems, detecting fraudulent reviews, and online profiling/privacy. Moreover, the use of a VP badge is immediately applicable to firms and platforms.

在线平台的评论系统创建了一系列在线口碑，使消费者可以从他人的购买经验中学习。但是，消费者很难辨别评论的真实性或评论者对产品的体验水平。在撰写评论的消费者已经验证购买了焦点产品的评论中，平台可以通过结合经过验证的购买（VP）指示或“徽章”来辅助身份验证过程。副总裁是对产品的偏爱，它暗示着效用最大化的选择，撰写评论的消费者对产品具有经验。将平板电脑上的Amazon数据集与在线评论中显示的偏好理论相结合，我们发现了令人惊讶的新结果：VP评论的比例（显示的偏爱）与更高的未来销量相关，而VP评论的比例对销量的影响主导了平均评分的影响。VP与揭示的偏好理论的这种新颖用法对推荐系统设计，检测欺诈性评论以及在线分析/隐私方面的新研究具有启示意义。而且，VP徽章的使用立即适用于公司和平台。