Interest-Focused Tutoring: A Tractable Approach to
Modeling in Intelligent Tutoring Systems
The University of Chicago, Computer Science Department
1100 East 58th Street, Chicago, Illinois 60637
Institute for the Learning Sciences, Northwestern University,
1890 Maple Ave., Evanston, Illinois 60201
Technical Report TR-96-08
Despite the progress made in the field of intelligent tutoring systems (ITS), it is still a major challenge to build systems that can teach about complex, ill-structured domains. A chief reason is that detailed, dynamic modeling of students' knowledge is intractable in such areas, and complete, correct models of expert knowledge are inherently difficult to build. These difficulties have led some to argue that the goal of intelligent tutoring should be abandoned and that more benefit could be provided by systems without tutoring. We believe that there are many areas in which tutorial intervention is essential, particularly for the communication of expertise.
In this paper we advocate basing tutorial intervention on an analysis of a student's likely points of interest within a learning environment, rather than on his or her state of knowledge. This interestfocused approach results in considerable simplification of the modeling task, and has other advantages as well. We describe an interest-tracing intelligent tutoring framework that we have been using to build learning environments for such ill-structured tasks as selling, managing, and other interpersonal skills using tutorial guidance. Our design is based on case-based reasoning as a model of human problem-solving. Expertise is modeled as an organized library of cases; student modeling is restricted to the considerations that enter into the decision to retrieve and present relevant cases.
This paper describes the cognitive theory underlying our tutoring approach, and the implementation of the tutor. We show how it is possible to present useful tutorial intervention based on a student's state of interest, without an overwhelming burden of student modeling.