Title:Playback-centric visualisations of video usage using weighted interactions to guide where to watch in an educational context

Abstract:The increase in use of online educational tools has led to a large amount of educational video materials made available for students. Finding the right video content is usually supported by the overarching learning management system and its interface that organises video items by course, categories and weeks, and makes them searchable. However, once a video is found, students are left without further guidance as to what parts in that video they should focus on. In this article, an additional timeline visualisation to augment the conventional playback timeline is introduced which employs a novel playback weighting strategy in which the history of different video interactions generate scores based on the context of each playback. The resultant scores are presented on the additional timeline, making it in effect a playback-centric usage graph nuanced by how each playback was executed. Students can selectively watch those portions which the contour of the usage visualisation suggests. The visualisation was implemented and deployed in an undergraduate course at a university for two full semesters. 270 students used the system throughout both semesters watching 52 videos, guided by visualisations on what to watch. Analysis of playback logs revealed students selectively watched corresponding to the most important portions of the videos as assessed by the instructor who created the videos. The characteristics of this as a way of guiding students as to where to watch as well as a complementary tool for playback analysis, are discussed. Further insights into the potential values of this visualisation and its underlying playback weighting strategy are also discussed.