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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Game@School. Teaching through Gaming and Mobile-based Tutoring Systems</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Sapienza Universita di Roma</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <fpage>46</fpage>
      <lpage>52</lpage>
      <abstract>
        <p>Keywords: Educational Games, Virtual Learning Environment, Intelligent Pedagogical Agent</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction and motivation</title>
      <p>
        Over the last ten years, the way in which education and training is delivered has
changed considerably with the advent of new technologies. The term \digital
native" coined by [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] in 2001, perfectly describes the nowadays students that
continuously deal with technology. Thus, technology should be a prominent part
of the learning process and should be intended as a support for teachers and
learners. One new methodology relying on present advanced technologies that
holds considerable promise for helping to engage learners is Games-Based
Learning (GBL). Games are well suited for developing students' scenario competence,
which can be de ned as the ability to imagine, enact and re ect upon
gamespeci c choices and their consequences, as Hangoj does in [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Unfortunately,
gaming and schooling have developed into two distinct \knowledge traditions"
that often rely on opposing validity criteria for determining what counts and
what does not count as relevant knowledge. To avoid that dichotomy, Game
Based Learning should integrate di erent aspects that are related to the
knowledge itself, to pedagogical aspects, to scenario-based and every day practise.
Following [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] we adopted the idea that there is a complex translation involved in
using games for educational purposes and thus we can see Game Based Learning
as a dynamic interplay of four knowledge practice, as depicted in 1. The model
is descriptive and assumes no a priori hierarchy between these four forms of
knowledge when teaching and playing games. However, in practice teachers and
students tend to value certain forms of knowledge, especially disciplinary and
school-only knowledge forms, as being more valid or serious than other forms of
knowledge.
      </p>
      <p>
        Actually, there are many e orts in the eld of Serious Games, discussing the
potential of games to provide new methods for supporting learning. At this stage
of the current research we can say that, respect to the past:
{ the importance and meaning of pedagogical foundation in educational design
is more clear to researchers [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]
{ the infrastructure of schools has developed a lot during the last decade
{ we are moving toward a new generation of educational use of games [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]
      </p>
      <p>
        In the described scenario has maturated the idea to develop a game in order
to teach STEM (Science, Technology, Engineering and Mathematics) subjects,
in particular physics. In this context, we followed the idea to integrate the most
up-to-date technologies in new teaching trends, namely Virtual Learning
Environments (VLEs, [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]) and Intelligent Pedagogical Agent (IPAs), as deeply
investigated in [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ].
      </p>
      <p>In particular, the developed Serious Game o ers:
{ A 3D virtual environment that the learner can explore and interact with.</p>
      <p>The student can collect objects, solve quizzes and setup experiments, all
related to the subjects of study.
{ An Intelligent Pedagogical Agent (IPA) that guides the learner throughout
the game. The learners can ask questions to the IPA and in such way,
personalize the learning path. In fact, students can express in free text and ask
whatever they want to the IPA, that will provide the best answer to the
posed question.
{ The IPA is emotionally intelligent, it performs a sentiment analysis on the
student sentence and assigns a tag (positive, negative or neutral) to the
sentence. Basing on the received tag the IPA behaves in di erent ways to
establish an emotionally safe relationship.
{ A shared knowledge forum in which students can share and discuss notes
about the learning objectives of the game.
{ An assessment tool in which the teacher can follow students engagement and
involvement during the game.
2</p>
    </sec>
    <sec id="sec-2">
      <title>State of the art</title>
      <p>
        The work in [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] presents a systematic literature review of empirical evidence
about the positive impacts and outcomes of games. Using the same search terms
used in that work, on a smaller number of databases,, the current update to the
systematic review of Boyle found many more papers reporting empirical evidence
of the positive outcomes of playing games (512) than the previous review (129).
This illustrates the increased interest in the positive impacts that digital games
had during the ve-year period from 2009 to 2014 compared to the previous
ve-year period.
      </p>
      <p>
        Regarding emotional learning, [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] presents an approach to modelling the user
a ect that is designed to assess a variety of emotional states during interactions.
Knowing the details of a users emotional reaction can enhance a system
capability to interact with the user e ectively. Instead of reducing the uncertainty in
emotion recognition by constraining the task and the granularity of the model,
the proposed approach explicitly encodes and processes this uncertainty by
relying on probabilistic reasoning. The authors discuss their model in the context
of the interaction with pedagogical agents designed to improve the e ectiveness
of computer-based educational games.
      </p>
      <p>
        [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ] presents a pedagogical agent capable of active a ective support, guided
by the logic that integrates the learners cognitive and a ective states. The
authors developed an algorithm for feature tracking, which utilizes a combination of
common image processing techniques, such as thresholding, integral projections,
contour-tracing and Haar object classi cation. The experimental results show a
range of preferences associated with pedagogical agents and a ective
communication. According to the authors, a ective interaction is individually driven, and
they suggest that in task-oriented environments a ective communication carries
less importance for certain learners.
      </p>
      <p>
        [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ], presents a system that embodies the idea of virtual humans that act
and interact like humans, bringing social elements in the interaction. A couple
of twins that are virtual teachers in the Museum of Science in Boston is
designed to engage visitors and raise their awareness and knowledge of science.
The twins have some aspects that were built in advance, and some that
operate in real time as the user interacts with them. The aspects built in advance
include the character bodies, animations, textual content, and spoken output.
The speech recognition, natural language understanding, and dialogue
management decisions of what to say are computed in real time, as is the scheduling
and rendering of spoken and gestural outputs. Speech recognition, natural
language understanding, and dialogue policies also make use of knowledge sources
constructed in advance, using supervised machine learning.
      </p>
      <p>
        In [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], the system allows the player to express himself in natural language.
The system processes users' input sentences and returns the best answer among
a set of possible stored answers. The communication is implemented through an
NLP (Natural Language Processing) algorithm based on an ad hoc text retrieval
problem solver and on a Naive Bayes text classi er with an inner product-based
threshold criterion. The algorithm implemented in the system is a variation of a
text retrieval algorithm. The system has been used in a quest game in which the
player can ask questions in free text to the Non Player Character to arrive to
the solution. We start from the result found by Mori to implement our dialogue
system.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Research questions</title>
      <p>
        Previous studies and literature appraisals suggest that educational games [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]
impact on learning as well as other behavioural and a ective outcomes, but also
point to the lack of empirical evidence to support several claims. Contrasting
opinions suggest that gami cation fosters shallow learning. But ultimately the
question of retention and how gami cation supports or undermines long-term
learning still remains open and further enquiry is needed [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. That considerations
lead to some open issues, like:
      </p>
      <p>RQ1: Does Educational Game support learning?
RQ2: Does Educational Game undermine long-term learning?</p>
      <p>RQ3: Does the use of Intelligent Pedagogical Agents foster the idea of
personalized mentors?</p>
      <p>In order to give my contribution to the above mentioned research questions,
the aim of my research is to develop a brand-new educational game and to
experiment it in the context of formal learning.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Advancement</title>
      <p>The boundary of the research described so far are quite wide and cover di erent
elds of research:
{ Pedagogy and psychology issues
emotion and learning
gaming and learning
role-play game
classroom practice
{ Arti cial Intelligent and Tutoring System</p>
      <p>Intelligent Pedagogical Agent
{ Virtual Learning Environment
3D Virtual World
Teacher's workplace</p>
      <p>Game engine
{ Game Based Learning</p>
      <p>Educational game</p>
      <p>
        The aim of that research is not to give an original contribution on each of
the listed research elds but, mainly, to integrate all the aspects in an original
and not yet existing educational game. First of all, as stated by [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ], currently
it does not exist a Serious Game that integrates Virtual Learning Environment
and Intelligent Pedagogical Agent and thus this is a very innovative point of
this research project. Secondly, the e ort in designing e-learning scenario or
serious game are more focused on kids or at University level, as it can be inferred,
for example, reading the proceedings of the 8th European Conference on Game
Based Learning. The high school domain is quite never considered while there is
a big interest in teaching STEM subjects in a di erent way also in high school.
Thirdly, the majority of the e-learning systems are intended for distance
teaching or used una tantum (like game) while the aim of the project is to change
the classroom practice using the developed game as a teaching tool like it could
be an e-book. Finally the majority of the existing Serious Game are not
specially designed but are re-adaptation of existing games, or even worst,
commercial games are used to teach STEM subjects, i.e. teaching physics with portal
2 (http://www.thinkwithportals.com/). Thus, we can say that the outcome of
the project will be a Serious Game that integrates new teaching trends and
paradigms making use of the most advanced technologies. From an engineering
point of view the challenges are:
      </p>
      <sec id="sec-4-1">
        <title>1. System architecture design</title>
        <p>2. Design and development of a Virtual Learning Environment
3. Design and development of an Intelligent Pedagogical Agent
4. Integration of VLE and IPA
5. Natural Language Processing
6. Emotion recognition</p>
      </sec>
      <sec id="sec-4-2">
        <title>From a pedagogy point of view the challenges are:</title>
      </sec>
      <sec id="sec-4-3">
        <title>1. Integrate emotional learning in the game practice</title>
        <p>2. Adopt a role-playing game as a model of collaboration and cooperation
3. Change classroom practice</p>
        <p>One of the game component, the IPA, has been tested in three di erent
schools between December 2015 and February 2016, involving roughly 50
students. In order to evaluate the use of the IPA, we developed a stand alone
Android application that make use of the IPA as interlocutor while studying
speci c subjects. The app came with two di erent learning paths developed by
eld experts and selected by teachers as possible insight. We decided to test the
IPA, before the entire game was nished, for several reasons. First of all the IPA
is an important component of the game and we wished to have feedback on its
usage and liking before nishing the game. Secondly the AI algorithm behind
the IPA needed to have a real validation to ne tuning its threshold. Finally
the IPA was easy to integrate in a stand-alone application. In this context we
tested appreciation, usability and learnability of the Android app in three
experimental sessions. The rst run of test validation occurred the 19 November 2015
(11 students, all males, aged 17-18), the second run occurred the 20 of January
2016 (16 students, two female, aged 17-18). After a preliminary evaluation of the
rst two test runs, we re ned the AI algorithm behind the IPA. The third run
occurred the 8 February 2016 (13 students, 8 males and 5 females, aged 17-18).
In all three runs, students were able to play with the application roughly 40
minutes (a bit less of a standard lesson time); we just asked them to play with
the application asking question to the IPA about the subject of study. After that
they compiled a questionnaire that has been structured in three main sections:
liking, usability and learnability.</p>
        <p>Appreciation. The rst set of questions aimed at understanding if students like
the idea of a personalized learning path and the possibility to ask free questions
guided by a virtual agent: 75 % of students like this possibility. The aspect of
the empathetic guide was felt as well: 68% of students liked the idea to have
an empathic guide and would like to chat also about personal matters. 68% of
students enjoyed the app and would recommend it to others, even if just 56% of
them perceived it as a game. 50% declared the app is more e ective for STEM
subject while the other 50% per cent said both STEM and humanistic.
Usability. It emerged that 68% nds the interface and the touch screen function
clear. Just 50 % of the students used the side menu and the majority of them
declare they wish to add other functionalities. Most of the interviewed disliked
the scientist avatar (70%) while liked the young girl (72%).</p>
        <p>Learnability. Tests revealed that 78% of students thought avatar explanations
are clear and declared that provided answers are in line with asked questions.
64% declared tips were useful. We asked how many questions they asked to the
avatar before quitting the game: 46% gave up after few questions, 34% ended
the game after roughly 10 questions, 15% around 20 and just 1 student declared
to ask more then 20 questions. Those results were obtained in the rst two runs.
That is mainly because very often pertinent questions received no answers due to
the very high threshold settings of the AI algorithm. However, after AI algorithm
threshold calibration, in the third test run we obtained that 38% ended the game
after roughly 20 questions while 30% gave up after few questions. So we had an
increment of roughly 20% in content exploration.</p>
        <p>The game will be fully tested in November 2016 with 100 students, however
the rst test runs have already proved that the developed Serious Game is
engaging for students and that the IPA can really help students in their personalized
learning path.</p>
      </sec>
    </sec>
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