Dissemination characteristics and influencing factors of topic circles in multi-layer public opinion dissemination.

Introduction: In recent years, social media has become a pivotal channel for public opinion dissemination, characterized by its multi-topic nature and dynamic complexity. Methods: This study utilizes data on public health incident dissemination from the Weibo platform as its research sample and, based on a multi-layered network model, proposes a framework for topic circle identification and dynamic network analysis in public opinion dissemination. The study explores the classification of user roles within topic circles, constructs a dynamic role transition matrix, and quantitatively analyses the impact of topic circle characteristics on dissemination volume. Results: The results indicate that core users exhibit significant stability and a dominant role within dissemination networks, while intermediate users display pronounced role mobility, and peripheral users are most sensitive to topic relevance. Furthermore, sentiment, forwarding enthusiasm, and forwarding depth exhibit significant differences in their effects on dissemination volume across different user roles. Discussion: This study enriches public opinion dissemination theory by examining the dynamic evolution of topics and user role transitions, providing practical guidance for managing and controlling public opinion dissemination on social media.