Online search advertising (aka, sponsored or paid search advertising) is a technology that any matched advertisement is displayed on Web pages as online users’ query results from search engines and Web portals (e.g., Google, Bing, Baidu, Naver, and Yahoo!). In specific, after online users type search keywords on the search box (at this stage, online users become searchers), search engines match users’ query texts to phrases included in search advertisement. Then, if an advertiser’s investment on her/his search advertisement is high enough, the advertisement is likely to be displayed on a search engine results (called “impression”) (Hanson and Kalyanam 2007; Jansen et al. 2009; Jansen and Clark 2017; Moore, Stammerjohan, and Coulter 2005). Once a searcher clicks a displayed advertisement and arrives on the advertiser’s landing page, s/he becomes a visitor by clicking the impression. As benefits of utilizing search keywords, online search advertising can reduce search costs and increase information accessibility by potential customers. In addition, because online search advertising provides relevant search results based on the users’ own queries, it is considered less intrusive than banner advertisement and widely used by many marketers (Ghose and Yang 2009; Johnson, Bruner, and Kumar 2006; Quinton and Khan 2009; Rangaswamy, Giles, and Seres 2009; Yang and Ghose 2010).

Digital channels have been rising to the major shopping paths from the past few years, yet it is interesting to notice that more and more digital retailers advance into offline channel nowadays due to the benefits. For example, the digital retailing giant Amazon opened its first bricks-and-mortar bookstore in 2015. Dell, which distributes its products only in the catalog and digital channels, entered the leading retail stores such as Best Buy and Walmart. The digital retailers’ strategy trend that moves into the real world reveals the unique and powerful capabilities of the offline distribution channel and the importance of launching products in the offline channel. Previous studies in marketing have investigated various complement and substitute impacts of offline channel introduction (i.e., Avery et al. 2012, Wang and Goldfarb 2017). However, most of the literature focus on the pc-based online channel and catalog, there is little research about the impact of offline channel introduction on smartphone-based mobile channel. Although mobile channel is similar to online channel in many ways (i.e., internet access and convenient shopping), it can be distinguished from online channel in terms of search and access, leading to a different interplay with offline channel. This research, therefore, aims to investigate how product launching in offline channel affects purchases in mobile channel versus online channel, and deepen the understanding by exploring the moderating effect of offline store intensity. Besides, we also explore the interaction between two digital channels: online channel and mobile channel. As most of the multi-channel retailers offer products in both online and mobile channels, it is incremental to know the interplay between these two digital channels. Using data from a representative multichannel retailer selling beauty products, we find the following three empirical results. First, product introduction in offline channel has a positive effect on online and mobile sales, and the effect is greater for mobile. Second, as offline store increases, the positive impact of offline product launch weakens on online channel, and even turns to negative once the number of offline stores reaches a threshold. However, the influence on mobile channel stays the same. The results reflect that the complementary interplay between offline and mobile channel is relatively stronger than between online channel. Finally, within the digital channels, online purchases only increase with the growth of sales performance within online channel, whereas mobile purchases are positively affected by both within mobile channel sales and across online channel sales. Our findings contribute critical academic and managerial implications for multichannel retailing.

Celebrity endorsement is defined as an agreement between a publicly recognized celebrity and an entity to use the celebrity’s fame to promote a brand or product. Generally, a celebrity is defined as a famous singer, actor, or athlete who frequently appears in public. The celebrity uses his/her public recognition to persuade consumers to purchase a specific product by the endorsement, and the celebrity accepts remunerations from the firm. Celebrity endorsement has been prevalent as an advertising strategy and many advertisers invest enormous amount of money for the celebrity endorsement. Prior research has examined the economic benefits or effectiveness of celebrity endorsement and found that celebrity endorsement attracts attention from consumers and polishes a tarnished brand image, and the celebrity may help advertisements stand out, thus improving their communicative ability. Apart from a general celebrity endorsement advantage, previous studies have found the factors that affect the success or failure of celebrity endorsement. An attractive celebrity can positively influence advertising evaluation, and a celebrity with expertise can increase consumers’ purchase intention through product. In addition, consumers prefer a product endorsed by a highly trustworthy celebrity. Specifically, on the economic worth of celebrity endorsement, most studies have indicated a positive effect. An announcement of a celebrity endorsement contract can bring a positive abnormal benefit to a firm’s stock price. Celebrity endorsement also helps increase the intangible value of a firm, which is the source of competitive edge and sustainable growth. However, despite recent interest in the return on advertising investment, it is not known how and which source factor of the celebrity endorsement can be explained with the firm value. By using text mining and sentiment analysis, the results of this study explain that the sustainable firm value is impacted by various sources of celebrity endorsement. First, the number of words regarding celebrity attractiveness, expertise, and trustworthiness has an impact on the sustainable firm value. Among the three sources, trustworthiness has the biggest impact on the sustainable firm value, which is Tobin’s Q. Second, regarding attractiveness and expertise, increasing proportion of positive words has impact on the firm value. On the other hand, regarding trustworthiness, the number of negative words on occupational issues is important. Third, different celebrity expertise has different impact on the sustainable firm value depending on the degree of job uniqueness and replaceability. Fourth, once the celebrity has lost his/her trustworthiness, the negative impact is hardly recovered as the negative interaction effect between positive impact of celebrity expertise on the sustainable firm value and the loss of trustworthiness is over seven times higher than the positive effects from the expertise. This implies that if an advertiser carefully manages other effects except for the loss of trustworthiness, he/she cannot offset the failure.