Rita, Paulo Miguel Rasquinho FerreiraRamos, Ricardo Filipe CarreiraMartins, Carolina Caldeira2024-03-252024-02-08http://hdl.handle.net/10362/165385Dissertation presented as the partial requirement for obtaining a Master's degree in Data Driven Marketing, specialization in Digital Marketing and AnalyticsExploring the relationships between social media platforms' characteristics, user motives, and outcomes is scarce. This study compares YouTube and TikTok while exploring the impact of video duration and ad irritation on purchase intentions and parasocial interaction mediated by entertainment, information-seeking, and wishful identification. To test the proposed hypotheses, two survey samples were collected from YouTube (n=274) and TikTok (n=142) fitness influencers' followers. The data was analyzed using partial least squares – structural equation modeling. The findings reveal that video duration significantly impacts all user motives on YouTube, whereas, on TikTok, only information-seeking and wishful identification were influenced. Surprisingly, ads irritation does not appear to influence user motivations on either platform. Additionally, all user motives are found to impact parasocial interaction. On the contrary, only information-seeking on YouTube impacts purchase intentions. Social media influencers and marketers must be aware of the video length and provide informational content and trustworthiness to ensure user engagement, sustained interest, and parasocial interaction.engFitness social media influencersUser motivesParasocial interactionPurchase intentionVideo durationSDG 3 - Good health and well-beingSDG 8 - Decent work and economic growthSDG 17 - Partnerships for the goalsmaster thesis203553691