Endorsement modes in social media advertising and the role of consumer involvement

Purpose In the context of social media advertising, the study investigates the effectiveness of different ways in which an endorsement is expressed i.e. endorsement modes (explicit, implicit, imperative, co-present) introduced by McCracken in his 1989 study. This study also aims to examine if consumer involvement moderates the effect of endorsement modes on advertising effectiveness. Design/methodology/approach The research used two experimental studies using fictitious Instagram posts (by a popular celebrity) to manipulate the endorsement modes. Study 1 tested the effectiveness of the endorsement modes in an ecologically realistic setting. Study 2 was aimed at providing internal validity by controlling for argument type and information load to isolate the impact of endorsement mode. The effectiveness of endorsement modes was assessed in terms of attitude toward the brand, attitude toward the advertisement and purchase intentions. Findings No significant effects of endorsement modes alone were observed. However, the two experimental studies consistently revealed a significant interaction of endorsement modes with CI. Explicit and imperative modes yielded more favorable brand attitudes under high CI; however, these benefits did not manifest under low CI. The results suggested that endorsement mode does have an impact on brand evaluations, independent of argument type and information load, although the impact is contingent on CI. Originality/value The paper extends endorsement literature by distinguishing the impact of endorsement mode from that of argument type and information load and by demonstrating that endorsement modes interact with CI in social media advertising. Using a muti-study approach, the study also refines Elaboration Likelihood Model-based expectations by suggesting that endorsement mode becomes particularly important under high CI.