Limits of graphic display design component variation based on cognitive tolerance for imprecision were investigated using compatibility functions. The compatibility function is an empirical definition of a perceptual category representing the grade of membership of an implied physical attribute into a corresponding conceptual category, measuring…

Argues that a computer-based programming tutor for novice programmers needs to take into account not only the types and frequency of bugs found in the programs, but the intentions and knowledge state of the programmer. A first version of such a program was developed on the basis of the bug types found in a number of pencil-and-paper studies with…

Different aspects of human-machine interaction are discussed in the five brief papers that comprise this report. The first paper, "Some Observations on Mental Models," discusses the role of a person's mental model in the interaction with systems. The second paper, "A Psychologist Views Human Processing: Human Errors and Other…

Individual papers discussing various facets of human relationships with interactive computer systems present an analysis of direct manipulation interfaces; discuss notion of conceptual models shared by system and user and propose a design methodology for delivering models to users; and address the intelligibility of systems and importance of…