The role of user models in cooperative interactive systems

For interactive systems to communicate in a cooperative manner, they must have knowledge about their users. This article explores the role of user models in such systems, with the goal of identifying when and how user models may be useful in a cooperative interactive system. User models are classified by the types of knowledge they contain, several user modelling characteristics that serve as dimensions for an additional classification of user models are presented, and user model representations are discussed. These topics help to characterize the space of user modelling in cooperative interactive systems—addressing how they can be used—but do not fully address when it is appropriate to include a user model in an interactive system. Thus, a set of design considerations for user models is presented, while a final example illustrates how these topics influence the user model for a hypothetical investment consulting system.