The main menu shows the options concerning the
domain (binary trees, AVL trees, and B trees),
didactic material for download, and an option to
activate the Help system and the following
submenus include concepts, tree operation
simulations and proposed exercises about insertion,
removal and search operations.
CoolED also presents chats to allow student
group discussion; a forum, which acts as a repository
of topics of interest for discussion, where students
and professors may participate; an agenda or
planner, where the professor posts deadlines for
activities and meetings; and an animated agent that
acts as a mediator in the collaborative process,
stimulating participation of all group members,
observing the development of activities, and
assisting the decision-making process as well.
4.2 The Agent
The agent is responsible for the student-environment
communication interface. It acts as mediator,
intervening when the student, for instance,
experiences difficulties in using a CoolED tool or in
conducting exercises and also when choosing the
group leader. The term mediator was constructed
from the concept of mediated relation described by
Vygotsky and is based on the behavioral analysis of
a teacher in a classroom who follows a social
constructivist approach.
In the developed prototype the agent’s figure is
represented by Peedy, an animated agent developed
by Microsoft that is available free of charge. Peedy
possesses a few movement functions, appearance
and text balloons. The remaining functionalities are
being developed by LAVI.
The following functions pertain to the agent:
Warning – shown to the students every time
new information is included by the professor in
the Planner, when material is available for
download, and when interest topics are inserted
in the Forum;
Assistance – provided whenever the agent
notices that a student faces difficulties in solving
the exercise, when there is lack of
communication between group members or when
communication is unilateral;
Correction – at the end of an exercise, the agent
compares the group answer to the exercise
solution;
Decision-making – for a solution of each
exercise, the agent uses the leadership model for
determining which student will lead the group.
4.3 CoolED’s Decision-making Process
In solving exercises collaboratively, group decision-
making is conducted by a leader, who is selected by
the agent, considering evaluation criteria described
in the leadership model. The student chosen as a
leader is the only one who conducts insertion,
removal and search operations in trees, and the role
of the remaining students is to participate in the
solution of the exercise, expressing their opinions
through the chat room.
In the model of leadership each student has a
leadership reputation grade that corresponds to the
probability of being chosen to be leader and a
variable that indicates how many times the student
has already been a leader. The system initially
bestows grade 5 to each student, hence all students
are equally likely to become leaders. As students
lead the exercises, their grades vary from 0 to 10,
where 0 means least likely to be chosen and 10
means most likely to be chosen. Grades start at 5
because, after each leadership, a student can have his
or her grade increased or decreased depending on his
or her performance. Whenever there is someone in
the group who has not yet been leader, this person
will always be chosen. The number of times a
student has been a leader will also be taken into
consideration, and priority is given to those who
were leaders the least often. In case of a tie between
the grade and number of times two people were
leaders, both will have the same chances of being
chosen, and the agent will randomly select one of
them.
At the end of each collaborative student-led
exercise, the group will answer an evaluation survey
that aims to analyze leadership performance, and
thus serve as a positive or negative weight for the
leadership grade. CoolED possesses two types of
surveys, one for group members lacking leadership
functions and another for leader self-evaluation. The
self-evaluation questions induce leaders to reflect on
their performance in this role and their interest in
repeating the experience. The other survey makes
the remaining participants of this work session to
analyze the leader’s role and investigate whether
they wish to work with this leader again. The result
after compilation is presented by the agent to the
leader.
4.4 Implementation
The CooIED system is in a final stage of
development taking as a basis the Document of
Requisites Specification, the Entity-Relation
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