Anais do IHC'2001 - Departamento de Informática e Estatística - UFSC

Anais do IHC’2001 - IV Workshop sobre Fatores Humanos em Sistemas Computacionais 37
(de Souza, 1993). It views a computer system’s interface as a unique one-shot metamessage
from designer(s) to users. It is one-shot insofar as the designer is no longer
available for carrying out a genuine two-way conversation with users about the conveyed
message. It is a meta-message, because it is itself capable of generating and exchanging
with users a number of messages about the interaction, and which make up the interaction
proper. It is also unique, because each computer application is built to solve particular
problems of a given domain, following a specific design strategy, which cannot be found in
its entirety in any other application.
By investigating the characteristics of interaction in different environments, one of
our goals is to analyze the advantages and disadvantages of having a single framework for
analyzing (and designing) interaction of a common range of services in different media and
environments. In order to guide our reflection about these issues, we present a case study,
through which we have reached some interesting conclusions and further questions.
In this paper, we apply linguistic studies of discourse structures and pragmatics to
an analysis of HCI phenomena in multiple environments. We do so while adopting the
semiotic engineering theoretical framework as the basis for our work.
In previous work (Dahis, 2001), we have developed a model for representing
interaction in such a way as to abstract details of specific interface styles and technological
constraints, following an interaction-as-conversation paradigm (Brennan, 1990). This
model, however, did not explore some relevant aspects of discourse structure nor
pragmatics. In this paper, we investigate how this model, coupled with some studies about
discourse structure (Gross & Sidner, 1986; Wachtel, 1986) and pragmatics (Leech, 1983),
could be used to analyze interaction for a single set of services in different environments.
2. Interaction Model
Dahis (2001) has proposed an interaction model for representing interaction-asconversation.
Her goal was to provide a common model for representing interaction at a
high level of abstraction, which could be instantiated into different environments and
interface styles. According to her, having a common interaction model would facilitate the
design and maintenance of these interfaces.
Dahis’ model was created to provide a means for modeling interaction scenarios in
a semi-formal representation. Her model represents interaction at three levels of
abstraction. From higher to lower levels, we have: tasks, dialogs, and utterances.
A task in this model represents how a real domain task may be accomplished using
the system, i.e. a complete interaction scenario. It encompasses one or more dialogs (stages
of interaction), which in turn are composed of utterances (units of interaction). She has
classified all elements into semantic types at each level, and created possible mappings
between levels. In order to do that, she devised one or more templates of dialogs and
corresponding utterances for any given dialog type. These templates were written in an
interaction scenario specification language she has created, called LECI.
A typical task specification in LECI would be: