Discusses the relationships between knowledge structure, teachers, and learners. Implications for designing an intelligent tutoring system (ITS) are considered; and it is argued that an ITS must model the world, the learner, and teacher-learner interaction to be successful. Experiments conducted to assess the practical usefulness of several…

Discusses the design and development of the user-computer interface in terms of the personal computer user's psychological needs and physical, perceptual, and conceptual contact with the system. Principles for the development of a user-system dialog that meets the requirements of transparency and visibility are suggested. Twenty-six references are…