The perturbation or buggy student model is depicted in figure 1.06. This model caters for knowledge possessed by the student that is not present in the expert domain knowledge.
Figure 1.06 : A representation of the perturbation or buggy student model.
The perturbation student model extends the experts knowledge with the addition of a bug library. The process to create a bug library can be enumerative or generative. The enumerative process lists all possible bugs usually via an analysis of the problem domain and the errors that students make. The generative approach attempts to generate bugs from an underlying cognitive theory.
An overlay model can the be applied over the combined expert knowledge and bug libraries. As with the simple overlay model the goal of tutoring is to grow the student’s subset of the experts knowledge while eliminating any bugs.
Authored by Serengul Smith
E-mail to:
serengul1@mdx.ac.uk
School of Computing Science Middlesex University
Revised: September 1998