Social media influencer marketing: the role of influencer type, brand popularity, and consumers’ need for uniqueness

The present study investigates how the type of social media influencer based on follower count (i.e. macro or micro-influencer) and the popularity of a brand that the influencer endorses affect consumers' purchase intentions for the endorsed brand. Results of four experimental studies demonstrate that consumers are more likely to purchase a more (less) popular brand when it is endorsed by a macro(micro)-influencer, because a macro(micro)-influencer is perceived as more congruent with the endorsement of a more (less) popular brand. Results further show that the higher effectiveness of a macro(micro)-influencer for a more (less) popular brand endorsement only holds for consumers who have a low need for uniqueness. Theoretical contributions and managerial relevance of the results are discussed.