Distinguishing user models from discourse models
Wolfgang Wahlster · 1988
P1. DM is a part of UM (e.g., Schuster) P2. DM intersects UM (e.g., Chin) P3. DM and UM are (e.g., Wahlster 1986, Cohen) Of course, interpretation of these positions depends on definition of terms involved and underlying notion of part-of, intersect, and distinct relations. relationships cannot simply be interpreted in a set-theoretic sense, since all definitions for UMs and DMs proposed so far depend not on representation structures, but also on processes used for construction, maintenance, and exploitation of these structures. Since this is a terminological, and not an empirical, discussion, as I pointed out in Wahlster (1986), P1-P3 are primarily normative statements. So, P3, for instance, must be interpreted as The terms UM and DM should be defined in such a way, that they do not overlap. This view seems not to be shared by all participants in discussion. Schuster, for example, tries to prove her position (PI) in a set-theoretic sense. First, she argues that the user contains information that does not appear in discourse model and then she proves that any information in discourse is also in user model. I disagree not with form, but also with content of Schuster's argumentation. She writes only if discourse is part of user can system take it into account in its responses and its reasoning about users. By considering an isomorphic argumentation like only if a tomato is part of cheese, can one use it to prepare pizza it becomes clear that this proof is flawed. Also, Morik points out correctly that if one follows