Roles of variables, which describe stereotypic usages of variables, can be exploited to facilitate teaching introductory programming. This paper describes the evaluation of visual metaphors for roles used in a role-based program animator. The evaluation is based on several criteria: properties of the images, metaphor recognition and grading, and effects on learning. The study demonstrates that as a whole the role metaphors facilitate learning. The results also identify ideas for further elaboration of the individual metaphors. Furthermore, the study suggests that the evaluation of animated metaphors may require special measures.

Visual metaphors in the form of still or animated pictures have been used in user interfaces with the hope of enhancing learning and use of computer applications. This paper studies animated metaphors with the intent to understand how they relate to human cognition and how their quality can be measured. We present a model of the relationships within metaphors, suggest lightweight evaluation techniques based on this model, and test these techniques in an empirical investigation. The results indicate that a lightweight analysis based on still images and made by domain-aware but metaphor-unaware judges can be used as a first step in deciding which metaphors are worthy of further study, and to direct animation efforts to overcome the most crucial problems. Furthermore, the results show that animation may increase or decrease the quality of a metaphor by considerable amounts; hence the final evaluation must be based on actual use of fully implemented metaphors. The results also confirm earlier suggestions to use rich metaphors and provides evidence that richness of the still image is important for the effectiveness of animation.

Roles of variables, which describe stereotypic usages of variables, can be exploited to facilitate teaching introductory programming. This paper describes the evaluation of visual metaphors for roles used in a role-based program animator. The evaluation is based on several criteria: properties of the images, metaphor recognition and grading, and effects on learning. The study demonstrates that as a whole the role metaphors facilitate learning. The results also identify ideas for further elaboration of the individual metaphors. Furthermore, the study suggests that the evaluation of animated metaphors may require special measures.