One of the most commonly used forms of video lectures is a combination of an instructor's image and accompanying lecture slides as a picture-in-picture. As the image size of the instructor varies significantly across video lectures, and so do the learning outcomes associated with this technology, the influence of the instructor's image size should be evaluated. This study tested the effect of image size of the instructor on learners' experience of social presence, cognitive load, learning performance and satisfaction. In the study, 87 Chinese undergraduates were randomly assigned to view a vid...
