Instagram influencers regularly promote products for brands. Some influencers follow Federal Trade Commission rules on advertising disclosures, such as putting "ad" or "sponsored" in a visible line of text, whereas others do not. Disclosures alert users that they are viewing an ad. Many social media users view influencers as authentic, trusted information sources, so it is important they are aware when viewing paid ads. How disclosures affect source credibility remains unclear. This study used 2 x 2 factorial design to evaluate the roles of two possible credibility enhancing factors: number of followers and advertising disclosures. Instagram users (N = 131) were shown an influencer's page and a corresponding post, then asked questions on credibility perceptions of the influencer, brand attitudes, intent to purchase the product, and intent to share the post. The results of a two-way MANOVA indicated that the main effect for followers was almost significant, F (4, 124) = 2.30, p = .06. The main effect for disclosure was not significant, F (4, 124) = 0.12, p = .98. Additionally, the interaction effect of followers and disclosure was not significant, F (4, 124) - 1.42, p = .23. These results indicated that number of followers and sponsorship disclosures do not impact credibility ratings or behavioral intent. However, 87% of respondents correctly identified the post as an ad, regardless of disclosure condition, indicating that Instagram users recognized advertising regardless of disclosure. Participants in both disclosure groups identified primary advertising indicators including photo layout, products, or brand recommendation. This research raises questions for future researchers regarding the role that disclosures and number of followers play in establishing source credibility and behavioral intent for Instagram influencer marketing campaigns.

Library of Congress Subject Headings

Instagram (Firm) -- Attitudes; Social media and society -- Attitudes; Social media -- Marketing; Internet marketing

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Faculty Advisor

Elizabeth Smith