A tool to support specification and evaluation of context-customized interfaces

• Authors: Fiorella de Rosis;Sebastiano Pizzutilo;Berardina De Carolis
• Venue: ACM SIGCHI Bulletin
• Year: 1996

Intelligent tools to support user interface building are being developed as a response to the difficulty of implementing interfaces of increasing complexity [1, 5, 6, 10, 7]. These tools provide expert assistance to insure that usable interfaces are developed correctly, by formalizing guidelines and criteria which are well known to experts. Less effort has been devoted so far to the objective of supporting the cooperative work of designers and final users in defining how the interface should look like and behave, in evaluating design alternatives and in assessing consequences of changes. This objective becomes relevant when the interface is built in strict cooperation with customers who are not familiar with computers, and by applying iterative design principles. At the same time, it is a common opinion that tools able to support formal evaluation of interfaces might be of help to avoid engaging into expensive empirical evaluations before trivial errors are eliminated from the prototype.A particular specification problem occurs when several categories of users, with distinct backgrounds and needs, are expected to use the system which is being designed: in this case, the interaction style is customized to the context in which the system operates, and the tool should enable simulating and evaluating the different behaviours in a unified way.This paper describes a tool which aims at responding to the mentioned objectives: XDM (Context-Sensitive Dialogue Modeling) extends Coloured Petri Nets to specify context-customized interfaces in a task-based way and to simulate their behaviour in defined contexts. By integrating this modeling approach with KLM theory [2], XDM also enables evaluating (in an automatic or semi-automatic way) whether the interface is correct and usable.First we will show how a designer can employ the tool in the stepwise building of the interface by extending Coloured Petri Nets with functions associated to places and transitions: this extension provides a logical and physical description of tasks performed, actions that enable performing them, information displayed and their layout. Then we describe how interface behaviour can be simulated in several contexts. We go on to show how designers can verify whether the interface is correct and usable. State of the art and future developments are discussed in the final section.