UC Davis

Short video platforms have emerged as key information sources, while the proliferation of misinformation on these platforms poses challenges for science and risk communication to adapt to emerging media formats and provide effective scientific surveillance on these platforms. This dissertation proposes that sensational short videos should be considered as an innovative solution to effectively communicate science and risk information in the current information ecosystem. Grounded on the theoretical framework of Message Sensation Value (MSV), this dissertation (a) investigates the relationship between MSV and public engagement and develops a computational measure of MSV with a computational observational study, and (b) examines the theoretical mechanism by which MSV in short videos impacts message attention, processing, and persuasiveness in the context of COVID-19 and climate change with an online experiment.Relying on a computational analysis of N = 1,200 short videos, the observational study reveals a consistent inverted U-shaped relationship between MSV and engagement, where videos with moderate levels of MSV are most engaging. This study also presents a computational measure of MSV using multimodal features with high reliability and validity. Built upon the insights in the observational study, the online experiment uses a within-subject experimental design and investigates the impacts of MSV (low, mid, high) in short videos for N = 1,467 participants in the United States. Results showed that MSV enhanced message processing and persuasiveness across varying belief congruence, while MSV did not affect attention or risk perception. In addition, contrary to existing research that emphasizes the impact of sensation-seeking and belief congruence, age was found to moderate MSV’s effects, which were particularly prominent for young adults. Overall, with both observational and experimental evidence, this dissertation demonstrates that MSV enhances message engagement and persuasiveness to a certain extent and suggests the possibility of leveraging sensational multimodal features in short videos to improve message persuasiveness and engagement for effective science and risk communication. This dissertation provides significant theoretical contributions and practical implications for communicating risks in the contemporary media landscape. First, this dissertation advances our understanding of MSV’s persuasive impacts and provides a useful theoretical framework for understanding multimodal information. Second, this computational measure of MSV provides a robust and automated tool for estimating MSV in short videos, facilitating the empirical research of short videos and MSV. Lastly, this study provides theory-informed practical implications and actionable guidelines for content production on short video platforms, which could increase the visibility of scientific information and establish scientific surveillance on short video platforms.