Examining the role of parasocial interactions in generating the bandwagon effect: a parallel mediation and multigroup analysis

Purpose The bandwagon effect – a psychological phenomenon where people embrace particular behaviours, purchase products or support trends simply because many others are doing the same – is emerging as an important concept in marketing literature. This study aims to investigate the role of parasocial interactions (PSI) in generating the bandwagon effect, using the parallel mediation of vicarious expression and electronic word of mouth (eWOM). Design/methodology/approach Framed within the context of parasocial relationship theory, this study used a purposive sampling method to collect data from 488 social media users who actively followed at least one tech YouTube influencer and one brand fan page on a social media platform, with a specific focus on the online retail sector. The collected data was analysed using partial least squares structural equation modelling and a multigroup analysis based on gender. Findings The results demonstrate that PSI with social media influencers significantly enhances mechanisms like vicarious expression experiences and eWOM, both of which emerged as key drivers of the bandwagon effect. Vicarious expression positively shapes consumer attitudes, while eWOM amplifies product and brand discussions within social networks. These mechanisms fully and parallelly mediate the relationship between PSI and the bandwagon effect. Practical implications This study offers various insights for brands, particularly those that operate online and/or are newly launched. The study showcases how the bandwagon effect for products and brands can be generated through the integrated influence of parasocial interactions with influencers, vicarious expression and eWOM. Originality/value This study uniquely identifies PSI, eWOM, vicarious expression and consumer attitude as key antecedents of the bandwagon effect, with vicarious expression and eWOM parallelly mediating the association between PSI and the bandwagon effect. It offers fresh insights into leveraging PSI with YouTube-based tech influencers to enhance vicarious product experiences and brand associations through engaging video content, highlighting its strategic potential for marketers.