Domain-specific knowledge representation and inference engine for an intelligent tutoring system

One of the most challenging steps in learning algebra is the translation of word problems into symbolic notation. This paper describes an Intelligent Tutoring System (ITS) that focuses on this stage of the problem solving process. On the one hand, a domain specific inference engine and a knowledge representation mechanism are proposed. These are based on a description language based on hypergraphs, and the idea of using conceptual schemes to represent the student’s knowledge. As a result, the system is able to simultaneously: (a) represent all potential algebraic solutions to a given word problem; (b) keep track of the student’s actions; (c) univocally determine the current state of the resolution process; (d) build a student model; and (e) provide adaptive automatic remediation. On the other hand, the Graphical User Interface (GUI) has been designed to force the student to follow the sequence of steps described in the Cartesian method. The ITS has been evaluated in an educational environment. The results show significant gains for the experimental group and hence support the use of the ITS in practice.