Beyond Lurking: Attitudinal Communities and Engagement Trajectories in Online Courses

Participation inequality is common in large-scale online courses, where many learners engage primarily by reading rather than posting on discussion forums. Although such learners are often labeled “lurkers,” this classification is typically based solely on observable activity. This study examines whether learners are clustered into distinct attitudinal communities based on shared perceptions of social presence, how these communities relate to behavioral engagement, and how these relationships evolve over time. Using discussion logs and three-wave survey data from large online courses, we classify learners by forum exposure (Posters vs. Viewers) and construct a social presence similarity network. Community detection reveals multiple attitudinal communities with robust, non-random structure. These communities show only partial alignment with behavioral participation and weak demographic stratification. Temporal analyses further indicate heterogeneous social presence trajectories within both Viewers and Posters. Together, these findings suggest that lurking reflects diverse experiential profiles rather than uniform disengagement, challenging participation-based interpretations of engagement in large-scale learning environments.