MODELING THE STUDENT IN PITAGORA-2.0

With the aim to individualise human-computer interaction, an Intellige nt Tutoring System (ITS) has to keep track of what and how the student has learned, Hence, it is necessary to maintain a Student Model (SM) dealing with complex knowledge representation, such as incomplete and inconsistent knowledge and belief revision. With this in view, the mai n objective of this paper is to present and discuss the student modell ing approach we have adopted to implement Pitagora 2.0, an ITS based o n a co-operative learning model, and designed to support teaching-lear ning activities in a Euclidean Geometry context. In particular, this a pproach has led us to develop two distinct modules that cooperate to i mplement the SM of Pitagora 2.0. The first module resembles a ''classi cal'' student model, in the sense that it maintains a representation o f the current student knowledge level, which can be used by the teache r in order to tune its teaching strategies to the specific student nee ds. In addition, our system contains a second module that implements a virtual partner, called companion, This module consists of a computat ional model of an ''average student'' which cooperates with the studen t during the learning process. The above mentioned module calls for th e use of machine learning algorithms that allow the companion to impro ve in parallel with the real student. Computational results obtained w hen testing this module in simulation experiments are also presented.