3.1.2 Tasks and Steps
The problems proposed to the learners are struc-
tured in tasks and steps. Classes ITSEGO:Task and
ITSEGO:Step must also contain all the information
needed to allow the execution of the Game-based ITS,
i.e., how the problem is presented (communicated) to
the learners. The base ontology we propose brings
with it a set of properties useful to link tasks and steps
with concrete resources (by using URIs). In this way
it is possible to deploy the system at different and het-
erogeneous learning environments.
Furthermore, the ITSEGO:Interaction class
provides a link to the specific environment (platform)
used to deploy tasks and steps, receive user inputs and
provide outputs.
Now, let us focus on two important aspects: topic
and content of a task/step. Tasks and steps need to
be associated to the content that must be proposed to
learners by using generic URIs. In addition, ITSEGO
provides a conceptual layer by means of the prop-
erty ITSEGO:topic connecting ITSEGO:Task (and
ITSEGO:Step) to skos:Concept that is the main con-
struct of SKOS
6
. SKOS is a Semantic Web ontology
allowing the definition of thesauri, taxonomies, con-
cept maps and so on. The conceptual layer enables
reasoning on topics and allows, for instance, to clas-
sify tasks with respect to their topics.
Lastly, tasks are not pre-ordered. The sequence of
tasks, proposed to the learner, can be obtained by ap-
plying specific pedagogical rules. One of the plausi-
ble solutions is to adopt the mastery learning strategy,
i.e., proposing tasks in order of increasing difficulties.
3.1.3 Context
The class ITSEGO:Context includes: student model
information and contextual information like, for in-
stance, environment or situation characteristics dur-
ing learners’ interactions with the system. The stu-
dent model is composed of three parts. The first one
includes student’s information (e.g., name, age), con-
textual information (e.g., family context, school con-
text), competency information (e.g., competencies al-
ready acquired), personal traits information. The sec-
ond one is characterized by information related to a
specific play like rewards (earned during the play),
competencies (acquired during the play), score (the
total score for the play) and performances (produced
during the play). The performances of a learner are
linked to specific game levels. Each game level has
a status (completed, not-completed, not-started) and
includes scores, rewards (that can be also badges) and
6
http://www.w3.org/2004/02/skos/
competencies (acquired) obtained by the player when
she faces this level. A game level is related to one or
more tasks (possibly belonging to the same difficulty)
that have to be successfully executed to complete the
level. The third one is characterized by information
related to affective and emotional states of the play-
er/learner. This information is dynamic and can be
“perceived” by processing raw data that comes from
additional sensors.
All the information included in the context can be
used by the pedagogical rules to adapt the experiences
and produce suitable and effective tutoring actions.
Moreover, some other data have to be gathered in ad-
dition to the previously indicated ones. For instance,
pedagogical rules can be based on number of errors
and number of consecutive errors for a specific step
and so on.
3.1.4 Tutoring Actions
Tutoring actions are the actions provided by tutors in
response to learners’ interaction with the content of a
specific step in a given task. Tutoring actions are se-
lected by considering several and heterogeneous as-
pects: context, pedagogical strategy, student’s emo-
tional state, student’s prior knowledge and so on. Tu-
toring actions can be classified in feedback, hints and
adaptations. ITSEGO provides further specializations
of the above mentioned classes. At each interaction,
only a subset of all plausible tutoring actions can be
provided.
3.1.5 Tutoring Rules
Tutoring or pedagogical rules implement the peda-
gogical strategy used to adapt the environment and
generate feedback/hint on the basis of the behavior
of the learner during her interaction with a step (in a
task) in a specific context. There are numerous ways
to implement such rules for an ITS. In this work, we
propose the development of such rules as class re-
strictions within ITSEGO. In this way it is possible
to generate the correct tutoring action (or set of tutor-
ing actions) by using standard OWL-DL reasoners.
The part of the ontology that is useful to model
and execute pedagogical rules is provided in Fig. 3.
The class ITSEGO:PedagogicalRule contains all the
admissible rules of the ITS (individuals). Each rule
is composed by a condition and an action (or more
actions) that must be executed when the condition
value is true. Conditions are individuals belong-
ing to ITSEGO:LearningCondition and are com-
posed by game state (task and step executed by the
learner), context (up to date information related to the
ITSEGO: An Ontology for Game-based Intelligent Tutoring Systems
241