DESIGNING CONCEPTUAL MODELS OF DIALOGS: A CASE FOR DIALOG CHARTS

Abstract

The conceptual design of user interfaces focuses on the specification of the structure of the dialog, independent of any particular implementation approach. While there is common agreement with respect to the importance of this activity, adequate methods and tools to support it are generally unavailable. The Dialog Charts (DCs) presented in this paper address this problem -- they support the conceptual design of dialog control structures. The DCs combine visual modeling (i.e., diagraming) with widely accepted design principles and an explicit model of dialog structures. As no clear evaluation criteria exist in this evolving area of dialog design, the preliminary assessment of the DCs takes the form of contrasting them with representative alternative design tools based on Augmented Transition Networks or Backus-Naur Form grammars. The DCs overcome some of the problems that seem to limit the usefulness of comparable approaches. An empirical investigation of the usable power of the DCs is currently underway at New York University, and a summary of this research activity concludes the paper.