Influencer marketing : instagram adverts by influencers and firms : comparative effects on purchase intention, brand attitude, and word-of-mouth

Abstract

Social media influencers affecting their follower bases on the popular picture-sharing platform, Instagram, is emerging as an effective communication strategy for brands. However, utilising firm advertisements on Instagram is also a prevalent alternative as it provides brands with precise audience targeting tools and full control of the message. Thus, today’s marketers face a strategic decision problem when considering marketing efforts on Instagram; should one use influencer adverts or firm adverts? With scholars yet to uncover the more effective choice on essential consumer responses, we address this decision problem by conducting an experiment with online questionnaires in collaboration with two recognized Norwegian Instagram influencers. Our quantitative analysis provides significant evidence that influencer adverts are more effective than firm adverts on brand attitude, purchase intention, and word-of-mouth. These effects are attributed to the influencers’ perceived source credibility, which is facilitated by trust and expertise being carefully crafted through interpersonal communication with followers over time. Also, high levels of credibility reduce the importance of the respondents’ attitude toward the advert and sustain the result of influencer adverts outperforming firm adverts. Ultimately, our paper provides valuable insight into influencer marketing, highlighting the importance of credibility in selection and collaboration with influencers. Keywords – Social media influencer, influencer marketing, Instagram marketing, social media marketing