My next few posts will consist of reviews of the literature in various advertising, public relations, and other communications journals on the topic of influencers. Influencer marketing, which involves a marketer inspiring or hiring social media content creators with large followings to spread the word about their products or services, has been exploding in recent years. Influencer Marketing Hub found that spending on influencer marketing increased to $4.6 billion in 2018 and was expected to be a $6.5 billion industry in 2019 from just $3 billion in 2017 and $1.7 billion in 2016. The influencer industry is considered to be mature, with 320 new entrants of influencer marketing-focused platforms and agencies during 2018, for a total of about 720 at that time. A study of 830 influencer marketing professionals found that three-fouths have increased their content output in the last two years, 60% had a standalone budget for influencer marketing in 2018, 92% see it as effective, and 63% intend to increase their budget in the near future.
What makes influencer marketing effective? To answer this question, we can draw on theories that have been developed to explain the effectiveness of advertising and/or communication and also theories of persuasion from psychology.
I’m starting with a review of articles from the Journal of Interactive Advertising (JIAD) for the past 10 years to see what theories have been applied, what variables and platforms have been studied, and the implications for future theory development. Only four relevant articles were found in JIAD. One study explored the factors that lead to effectiveness of the influencer, another examined the development of parasocial interactions, and two discussed the impact of disclosure statements used by influencers on the effectiveness of the influencer.
In 2019, JIAD published Chen Lou and Shupei Yuan’s article titled “Influencer Marketing: How Message Value and Credibility.” The authors used McGuire’s communication-persuasion matrix as a theoretical framework, which explores the elements of source, message, channel, receiver, and destination on the effectiveness of a message. In their study, Lou and Yuan surveyed participants and asked them to consider an influencer they follow without specifying the platform. They focused specifically on McGuire’s source and message variables and examined information value and entertainment value of the message and expertise, trustworthiness, expertise, attractiveness, and similarity of the influencer. Moderating the relationship between these variables and the outcomes of brand awareness and purchase intention were trust in the post. This study found relationships between the information value (not entertainment value) of the posts and the trustworthiness, attractiveness, similarity (not expertise) of the source with trust in the posts, which led to brand awareness and purchase intention. Through their findings, Lou and Yuan proposed the integrated social media influencer value model.
The next most recent article in JIAD related to influencers was the 2018 article titled “The Influence of Social Media Influencers: Understanding Online Vaping Communities and Parasocial Interaction through the Lens of Taylor’s Six-Segment Strategy Wheel” by Emory S. Daniel, Elizabeth C. Crawford Jackson, and David K. Westerman. The theoretical framework for this study was Taylor’s Six-Segment Strategy Wheel (SSSW) and the researchers examined whether it was relevant to discussions in the vaping community found in the comments of videos published in the Vape Capitol YouTube Channel and also whether parasocial interactions were present. The researchers found categories of the SSSW to be present in 42% of comments, with the ritual side representing 86.3% present of those comments and the transmission side representing 13.7%. Parasocial interactions were also present in 68% of comments. The authors propose a model whereby social strategies, such as having a relevant and likable influencer, lead to feelings of parasocial interactions, which can lead to feelings of a parasocial relationship after repeated interactions, and then finally brand loyalty, sales, and word of mouth.
The next two studies deal with the impact of disclosure statements on the effectiveness of an influencer. In the 2017 study “Disclosing Instagram Influencer Advertising: The Effects of Disclosure Language on Advertising Recognition, Attitudes, and Behavioral Intent,” authors Nathaniel J. Evans, Joe Phua, Jay Lim, and Hyoyeun Jun applied the persuasion knowledge model (PKM) by Friedstad and Wright. This approach focuses on the persuasion knowledge of consumers to recognize persuasion attempts and then how they select and implement coping strategies to deal with those persuasion attempts. Messages that are deemed persuasion will be processed differently than those not considered persuasion, according to PKM. In this Instagram study, variables included exposure to advertising disclosure and whether it leads to higher advertising recognition. Also explored was disclosure through the words “Paid Ad” and “Sponsored” as compared to “SP” and the impact on attitudes, purchase intention, and intention to spread electronic word of mouth messages as well as advertising recognition, which was measured as a mediator between the disclosure and the other effects. The research found that disclosure produced more advertising recognition, with “Paid Ad” and “Sponsored” more likely to be recognized than “SP” or no disclosure. Attitude toward the brand was found to be significantly higher for no disclosure, but there were no significant differences for the other variables. An interaction between disclosure recall and advertising recognition produced a negative indirect effect on attitude toward the brand and intention to spread eWOM, but not purchase intention.
In 2014, JIAD published “The Effect of Disclosure of Third-Party Influence on an Opinion Leader’s Credibility and Electronic Word of Mouth in Two-Step Flow Theory” by Caleb T. Carr and Rebecca A. Hayes. Like this previous study, this study also looked at disclosure of third-party influence, but in blogs instead of Instagram. Katz and Lazarsfeld’s two-step flow model, which predicts that the media influence opinion leaders who pass information to their social groups, provided the theoretical framework for this study. Variables in this study of online product reviews (formatted as blog posts) included mention of third-party influence and the effects on perceived credibility, and then the impact of perceived credibility on perceived word-of-mouth influence. The lowest credibility levels resulted from tacit implications of third-party content influence and the highest credibility levels results from explicitly disclosing influence. Perceived credibility was found to be positively related to perceived word-of-mouth influence.