The Expression of Certainty in Live Streaming: A Comparative Analysis of Epistemic Stance Between Professional Streamers and College Students

Epistemic stance is adopted as an approach to convey the speakers’ certainty about knowledge and beliefs. This research aims to make a comprehensive comparison between professional live streamers and Chinese college students in terms of epistemic stance expression in their live streaming. Focusing on three distinct product categories—fashion, food, and home and electronics—the research collected texts from Amazon live streamers’ online broadcasts and Chinese college students’ in-class live streaming training. The investigation employed epistemic stance features derived from Hyland’s model, utilizing 76 stance features categorized as boosters or hedges for analysis. The results revealed that both professional live streamers and college students used boosters significantly more than hedges when expressing epistemic certainty, along with a distinct co-occurrence pattern of self-referential expressions (e.g., I, we) combined with boosters. However, there were statistically significant differences between the two groups in the use of epistemic stance expressions. Professional streamers demonstrated higher frequencies of epistemic devices overall, which was observed in three parts of speech (adverbs, modals, and verbs) and across three product categories. These findings have theoretical significance for advancing study of stance expression and pedagogical implications for business English applied in live streaming training context.