How day of posting affects level of critical discourse in asynchronous discussions and computer-supported collaborative argumentation

In asynchronous threaded discussions, messages posted near the end of the week provide less time for students to critically examine and respond to ideas presented in the messages than messages posted early in the week. This study examined how the day in which messages are posted (early, midweek and weekend) in computer-supported collaborative argumentation affect the number of responses elicited by arguments and challenges, and how its effects differ across the four types of exchanges (argument–challenge, challenge– counterchallenge, challenge–explain, challenge–evidence) that serve as indicators of critical discourse. This study found that the day of posting had a significant effect on the number of responses elicited per message, with the greatest to smallest effect on argument–challenge, challenge– counterchallenge, challenge–explain and challenge–evidence exchanges respectively. These findings highlight some of the limitations of asynchronous discussions, and suggest alternative ways to implement and design discussion environments to promote higher levels of critical discourse