Search advertising, the paid listings on a search engine website based on consumers’ keyword searches, has become one of the most important advertising formats and have thus received a huge amount of attention from both academics and practitioners. While many researchers have studied search advertising in a single keyword framework, in practice, consumers’ search usually involve multiple keywords related to their purchase, and similarly, firms advertise on a set of related keywords. Thus, understanding a utilization of multiple keywords is important for firms to efficiently allocate their advertising budget to each keyword, based on consumers’ decision of which keywords to search and which advertising to click. Therefore, this study aims to examine consumers’ search behavior in terms of their click decisions and retailers’ bidding strategy over a set of related multiple keywords. We empirically examine the aforementioned issues regarding consumer clicks and advertiser bids in a search advertising campaign. We use in our empirical analysis a unique dataset containing a number of related keywords in a running shoes product category, in which consumers frequently make online purchases, pertaining to two leading brands in the product category, Nike and Adidas. Based on the consumer purchase funnel framework, we have classified the keywords into five keyword groups at three different levels, the category, brand, and model level keywords. Our data contain daily information from 242 online retailers on their search advertising metrics such as payments per clicks, bids, quality scores, ranks, and the number of clicks from September 1, 2012 to November 30, 2012. Our empirical findings show that overall, consumers search for keywords in a manner consistent with purchase funnel, although some inconsistencies exist in the detailed behavior, depending on different keyword groups and brands. Our findings also show that retailers simultaneously bid on multiple keywords at different stages of the consumer purchase funnel, suggesting that retailers regard the different keywords as strategic complements. However, our findings suggest that retailers’ allocation of their bids across multiple keywords are often inconsistent with the consumer search behavior. Those findings provide advertisers with new insights on multiple keyword management to develop and implement a more effective search advertising strategy.

• Alex Jiyoung Kim(Ewha Womans University, Republic of Korea)
• Sungha Jang(Kansas State University, Kansas, USA)
• Hyun S. Shin(Hanyang University, Republic of Korea)