Social media advertising endorsement: the role of endorser type, message appeal and brand familiarity

In an investigation of social media ad endorsers' successful effects, this study examines congruity effects between endorser type (celebrity vs. social media influencer [SMI]), message appeal (soft sell vs. hard sell), and brand characteristics (familiar vs. unfamiliar). To that end, an experiment was conducted with 351 participants, and the results indicated match-up effects between SMI and hard-sell appeal in brand attitude and purchase intention. Also, an SMI is a better match with familiar brands than a celebrity endorser in terms of purchase intention. Furthermore, a significant three-way interaction effect was found so that the congruity effects between endorser type and message appeal on brand attitude are more pronounced with familiar brands than with unfamiliar brands. As expected, endorser characteristics play a mediating role between endorser type and advertising effectiveness. Furthermore, theoretical and managerial implications are discussed.