From herd effect to impulsive buying behaviour on TikTok: The moderating role of parasocial relationships

Abstract

This study examines the impact of herd effect on impulsive buying on the TikTok platform in Vietnam, while also investigating the moderating role of parasocial relationships between users and influencers. Grounded in the Stimulus - Organism - Response (S-O-R) framework, bandwagon effect theory, and parasocial interaction theory, the study proposes and tests a research model with three hypotheses. Data were collected from 376 young TikTok users in Vietnam and analysed using the PLSSEM method. The results indicate that herd effect has a positive effect on impulsive buying (β=0.191). In addition, parasocial relationships with influencers exert a direct positive influence on impulsive buying (β=0.336). More importantly, parasocial relationships positively moderate the relationship between herd effect and impulsive buying (β=0.267). This study contributes to clarifying the combined mechanism of social influence and emotional attachment in shaping impulsive buying behaviour in social commerce contexts.