An Assessment of Visual Representations for the ‘Flow of Control’

Historically, graphical programming and visual programming most commonly used arrows, lines or juxtaposition to represent visually the order or a sequence of actions. The choice of representation can affect the performance of a user of such systems in following a sequence of actions, both in terms of time and of accuracy. However, there is little empirical evidence which would justify the use of one representation over the other. This paper addresses these issues and examines what should govern the choice of representation for the ‘flow of control’. An experimental study that compares how the three representations affect users’ performance is conducted on several groups of undergraduate students. The result suggests that arrow is the best performer and that juxtaposition is the most error-prone.