Earnings Announcement Promotions : A Yahoo Finance Field Experiment

This study presents a field experiment we conducted in which media articles for a random sample of firms with earnings announcements are promoted to a one percent subset of Yahoo Finance users. The promoted firms have similar fundamental and earnings-news characteristics as control firms, yet we find that promoted firms have higher abnormal returns on the day of the earnings announcement, and some evidence of lower bid-ask spreads. Moreover, these results are more pronounced for less visible firms, negative earnings news, and on days with fewer promoted firms. We do not find evidence of significant increases in trading volume, or of information acquisition by users subject to the promotion. These findings suggest that investor attention affects the pricing of earnings and that retail investors buy stocks that catch their attention, in a setting where attention is randomly assigned