The development of a theoretical framework and design tool for process usability assessment.

The purpose of usability engineering is to facilitate the deployment of new products by decreasing development costs and improving the quality of systems. This paper will discuss the development and delivery of a unique, theoretically based software tool that provides engineers and designers with easy access to the most recent advances in human-machine interface design. This research combines several theoretical views of the interaction process into a hybrid model. Based on this model, a software tool was produced that allows engineers to model the human interaction process within their design. The system then provides feedback on the interaction process through items such as: the amount of mental effort required by a user, the degree to which the system conforms to human capabilities, the expected time to complete the interaction, where potential human error may occur, as well as potential misunderstandings or points of confusion to the users. The designer may then use this information to improve the design of the system. Validation of this technique indicates that the hybrid model produces accurate predictions of usability attributes and that the technique transfers from the laboratory to the real world.

The implementation and evaluation of a theory for high level cognitive skill acquisition through expert systems modelling techniques.

From previous studies by Koubek and Salvendy (1988), it has been established that differences exist in the high level controlled processes between expert (E) and super-expert (SE) subjects on computer program modification tasks. This study examines the implications of this finding by applying modelling techniques via expert systems technology. To examine the hypothesis that the knowledge representation is critical to SE performance, and to indicate how these results might have practical application, two small prototype expert systems were developed using the E and SE knowledge representations respectively. A qualitative analysis reveals significant performance differences between systems attributable to the knowledge representation and suggests a combination of E and SE knowledge be used for construction of a hybrid expert system. The SE knowledge base is a hierarchical structure and is organized under abstract categories, suggesting a breadth first approach. This structure allows for interactions within the program itself and between the program and user environment. The E knowledge base is narrow and task specific, indicating a depth first approach. In conclusion, theoretical and practical implications of this research into SE performance and modelling techniques are discussed.