A Multimodal Emotion Perspective on Social Media Influencer Marketing: The Effectiveness of Influencer Emotions, Network Size, and Branding on Consumer Brand Engagement Using Facial Expression and Linguistic Analysis.

This article examines how emotional expression in facial cues and caption text by social media influencers (SMIs), specifically prominent Instagram mother influencers known as InstaMoms, affects consumer engagement measured by likes, comments, and views. Using facial expression analysis, computational linguistic analysis, and social media analytics on 402 video posts, the study finds that facial emotional expressiveness significantly increases consumer engagement, whereas textual emotion alone does not. The influence of emotion varies with follower count and branding: negative facial emotions (anger, sadness) drive engagement more effectively for influencers with smaller followings and unbranded posts, while larger follower counts are necessary to leverage emotion successfully in branded content. These findings highlight the nuanced role of discrete emotions, follower network size, and commercial branding in shaping influencer marketing effectiveness.