Paid media expenditures could potentially increase earned media exposures such as social media posts and other word-of-mouth (WOM). However, academic research on the effect of advertising on WOM is scarce and shows mixed results. We examine the relationship between monthly Internet and TV advertising expenditures and WOM for 538 U.S. national brands across 16 categories over 6.5 years. We find that the average implied advertising elasticity on total WOM is small: 0.019 for TV, and 0.014 for Internet. On the online WOM (measured volume of brand chatter on blogs, user-forums, and Twitter), we find average monthly effects of 0.008 for TV and 0.01 for Internet advertising. Even the categories that have the strongest implied elasticities are only as large as 0.05. Despite this small average effect, we do find that advertising in certain events may produce more desirable amounts of WOM. Specifically, using a synthetic control approach, we find that being a Super Bowl advertiser causes a moderate increase in total WOM that lasts 1 month. The effect on online WOM is larger, but lasts for only 3 days. We discuss the implications of these findings for managing advertising and WOM.

中文翻译：

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您的广告能否真正购买获得的展示机会？品牌广告对口碑的影响

付费媒体支出可能会增加获得的媒体曝光率，例如社交媒体帖子和其他口碑（WOM）。但是，关于广告对WOM的影响的学术研究很少，而且结果不一。我们研究了6.5年中16个类别的538个美国民族品牌的每月互联网和电视广告支出与WOM之间的关系。我们发现，在总WOM上平均隐含的广告弹性很小：电视为0.019，互联网为0.014。在在线WOM（测得的博客，用户论坛和Twitter上的品牌聊天量）上，我们发现电视的平均月度影响为0.008，互联网广告的平均月度影响为0.01。即使具有最大隐含弹性的类别也只有0.05。尽管平均效果很小，我们确实发现，在某些事件中投放广告可能会产生更理想的WOM数量。具体而言，使用综合控制方法，我们发现作为超级碗广告商会导致持续1个月的总WOM适度增加。对在线WOM的影响较大，但仅持续3天。我们讨论了这些发现对管理广告和WOM的意义。