RT Journal Article SR Electronic T1 A Comparison of Social Media Influencers’ KPI Patterns across Platforms JF Journal of Advertising Research JO J Advert Res FD WARC SP 139 OP 159 DO 10.2501/JAR-2023-008 VO 63 IS 2 A1 Naser Pourazad A1 Lara Stocchi A1 Shreya Narsey YR 2023 UL http://www.journalofadvertisingresearch.com/content/63/2/139.abstract AB Brand managers increasingly incorporate influencer marketing in their marketing strategies, but methods for evaluating the effectiveness of influencers and choosing the best personalities to collaborate with are unreliable. This study addresses this shortfall by examining classic key performance indicators (i.e., the number of followers and engagement rate) of 180 influencers on Facebook, Instagram, YouTube, TikTok, and Twitter. The analysis is based on a sample of more than 35,000 posts and considers the influencers’ areas of expertise. Among the key findings, the authors detected differences in double jeopardy effects (reverse, classic, and no double jeopardy) among mature, growing, and changing social media platforms. The findings carry practical implications for establishing partnerships between brands and influencers.