Arguing that understanding what lies behind the apparent usability of direct manipulation style interfaces might not only help in building better interfaces, but can also draw attention to possible side effects, this paper uses examples from a prototype data manipulation system to pursue a characterization of direct manipulation interfaces as…

This paper reviews briefly the essential characteristics of both invitational education and computer assisted instruction (CAI) and the ways in which coordination of these two models can produce stimulating and valuable educational experiences for students. A matrix illustrates the characteristics of CAI which can support the major values of…

Several text format variables were examined in an attempt to identify the ways in which these variables interact in specific design combinations. The variables include: heading location (embedded or isolated); line length (short or long); space between lines (single or double); paragraph indication (indented or spaced); use of running heads…