The Impact Factor of Influencers - Modeling a new indicator for the tourism sector

Social media and influencers play a crucial role in inspiring tourists and shaping travel decision-making processes. Empirical evidence suggests that the likelihood of planning a trip based on User-Generated Content (UGC)—that is, content created by individuals rather than organizations—is approximately 48%, as such content is perceived as more trustworthy and authentic than brand-generated content. Influencer marketing, widely recognized as a dominant paradigm on social media, is considered one of the approaches most likely to shape the future of social media marketing (Vrontis et al., 2021). Current influencer campaign performance metrics primarily rely on indicators such as views, publication reach, and engagement rates. This article proposes an alternative framework for measuring influencer marketing campaigns based on network analysis techniques. Using data collected from three influencer marketing campaigns conducted on tourist destinations through Instagram, this study develops an algorithm-based composite indicator, referred to as the Impact Factor, designed to assess an individual's influence by combining measures of credibility (authority score) and visibility (hub score). Based on the cases examined, our approach enables the mapping of influence networks, the assessment of relationship quality within influencer campaigns in addition to their quantitative reach, and the identification of the most influential individuals best suited for digital marketing campaigns.