(Georgia Institute of Technology, 1998)
Ram, Ashwin; Catrambone, Richard; Guzdial, Mark; Kehoe, Colleen Mary; McCrickard, D. Scott; Stasko, John T.
A central issue in the development of multimedia systems is the presentation of the information to the user of the system and how to best represent that information to the designer of the system. Typically, the designers create a system in which content and presentation are inseparably linked; specific presentations and navigational aids are chosen for each piece of content and hard-coded into the system. We argue that the representation of content should be decoupled from the design of the presentation and navigational structure, both to facilitate modular system design and to permit the construction of dynamic multimedia systems that can determine appropriate presentations in a given situation on the fly. We propose a new markup language called PML (Procedural Markup Language) which allows the content to be represented in a flexible manner by specifying the knowledge structures, the underlying physical media, and the relationships between them using cognitive media roles. The PML description can then be translated into different presentations depending on such factors as the context, goals, presentation preferences, and expertise of the user.
(Georgia Institute of Technology, 1996)
Byrne, Michael Dwyer; Catrambone, Richard; Stasko, John T.
Two experiments examined the general claim that animations can help students learn algorithms more effectively. Animations and instructions that explicitly required learners to predict the behavior of an algorithm were used during training. Post-test problems were designed to measure how well learners could predict algorithm behavior in new situations as well as measure learners' conceptual understanding of the algorithms. In Experiment 1, we found that when learners both viewed an animation and made predictions, their performance on novel problems improved comapred to a control group's, but the effects of the two manipulations were not distinguishable. In Experiment 2, no effect was found for conceptual measures of learning, but a marginally reliable effect similar to the one seen in Experiment 1 was found for procedural problems. The results from the two experiments suggest that the benefits of animations are not obvious and that in order to determine whether animations can truly aid understanding, teachers and researchers should consider a careful task analysis ahead of time to determine the specific pieces of knowledge that an animation can help a learner acquire and/or practice.