HUMAN-FACTORS ISSUES IN DIALOG DESIGN

This chapter focuses on the human factors of the engineering-design principles for design of dialog with computers. Measurements of human performance are traditional in human-factor engineering. Typically, an interface or a dialog style will be evaluated in a laboratory setting by bringing in test subjects and having them perform a task on a computer. The chapter highlights that the human-factors design of computer systems has became increasingly important, and manufacturers of computers and software have come to realize that unless their products are easy to use, they will probably not sell. One of the major problems is that the characteristics of the user population vary tremendously. In evaluating different command languages, menu styles, and so forth, subjects participate in formal experiments based on scientific hypotheses or theories, where several design alternatives are evaluated. The chapter gives an overview of the following types of dialog: command language, menu, query language, natural language, and windows. The chapter illustrates that the principles of good command-language design extend to any dialog style where names are used to represent options or actions. It also describes several advantages and disadvantages of command languages and menu systems and describes factors affecting user performance. The chapter also discusses about query language, natural language, and windows, highlighting their advantages disadvantages and user interface issues. The chapter ends with a discussion on principles for design, principles for evaluation and, the need for research. © 1991 Academic Press Inc.