Student Modeling for Personalized Education: A Review of the Literature - Advances in Personalized Web-Based Education - page 4

Fig. 1.3 Overlay model
characterized by a qualitative measure (good-average-poor) or a qualitative measure
such as the probability that the student knows the concept (Brusilovsky and Millán
2007). This kind of representation informs the system about the degree to which the
learner knows each domain element.
1.2.2 User Stereotypes
Stereotypes were introduced to user modeling by Rich (1979). The main idea of
stereotyping is to create groups of students with common characteristics. Such
groups are called stereotypes. A learner will be assigned into a related stereo-
type if some of his/her characteristics match the ones contained in the stereotype.
For example, a stereotype model can present the knowledge lever (Fig. 1.4 ) or the
learning style of a student. In these cases the stereotypes could be {novice, beginner,
knowledgeable, advanced, expert} and {visual, verbal} accordingly. Each stereo-
types has a set of trigger conditions, which activate the stereotype if they are true,
and a set of retraction conditions, which deactivate the stereotype if they are true
to Kay (2000). The stereotype is a particularly important form of reasoning about
users and also student modeling with stereotypes is often a solution for the prob-
lem of initializing the student model by assigning the student to a certain group of