Temporal, social, and dialogical characteristics of asynchronous online discussions and their implications for design

Asynchronous Online Discussion (AOD) is widely adopted in university courses. The rapid expansion of AOD challenges educational research to develop an understanding of how students interact and learn in this medium to inform instructional and pedagogical design. This dissertation reports three empirical studies investigating temporal, social, and dialogical aspects of AOD in a fully online undergraduate history course. Log data, discourse data, and achievement data were collected and assembled in a database. Study 1 (Chapter 3) is a visualization study of temporal features of discussion participation in a total of 22 discussions in the course. The study compared temporal patterns associated with different discussion formats, group configurations, and achievement groups and identified contextual factors that had impact on discussion participation. Design implications for instructional design were proposed such as setting discussion durations and otherwise structuring the temporal structure of discussion activities, as well as strategies for enhancing students' motivation to engage with AOD in a timely manner. Study 2 (Chapter 4) used Social Network Analysis (SNA) and content analysis to investigate social network patterns in relation to knowledge construction outcomes and achievement. The study extracted a predictive factor comprising five social network variables representing group connectivity which correlated strongly with group knowledge construction practices. Implications for promoting triadic interactions and knowledge negotiation are discussed. Taking a systemic functional linguistic perspective, Study 3 (Chapter 5) investigates how linguistic resources in discussion posts are associated with different discussion formats, and how the linguistic resources engage dialogic interaction and influence uptake of information. Based on engagement resources, information uptake, and discussion participation, students fall into three clusters characterized with different interaction styles. The implications for discussion design, requirements, guidelines, and grading rubrics to foster students' awareness of dialogic functions of language use are discussed. Findings from the three studies point to the need to address students' intrinsic motivation. Structuring rich temporal-relational contexts to support students' agentic control of time use, promoting students' sense of integration in social learning and collaboration, and enhancing students' experience of autonomy and competence in discussions are key to successful learning design of asynchronous discussion.