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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>The first five editions of the PALE workshop led to the Special
issue on User Modelling to Support Personalization in Enhanced
Educational Settings in the International Journal of Artificial
Intelligence in Education (IJAIED) [1].</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>8th International Workshop on Personalization Approaches in Learning Environments (PALE 2018) Preface</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Milos Kravcik</string-name>
          <email>Milos.Kravcik@dfki.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Maria Bielikova</string-name>
          <email>maria.bielikova@stuba.sk</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Olga C. Santos</string-name>
          <email>ocsantos@dia.uned.es</email>
          <xref ref-type="aff" rid="aff5">5</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jesus G. Boticario</string-name>
          <email>jgb@dia.uned.es</email>
          <xref ref-type="aff" rid="aff5">5</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Tomas Horvath</string-name>
          <email>tomas.horvath@inf.elte.hu</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ilaria Torre</string-name>
          <email>Ilaria.Torre@unige.it</email>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Personalization, Adaptive Learning Environments, Engagement,</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Context Awareness</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Educational Technology Lab, DFKI, GmbH</institution>
          ,
          <addr-line>Berlin</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Eötvös Loránd University Hungary</institution>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Slovak University of Technology in</institution>
          ,
          <addr-line>Bratislava</addr-line>
          ,
          <country country="SK">Slovakia</country>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>TEL&amp;DH Research Group, DIBRIS, Genoa University</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff5">
          <label>5</label>
          <institution>aDeNu Research Group</institution>
          ,
          <addr-line>UNED</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <abstract>
        <p>Personalization is a well-established topic in education and there have been over 30 years of experience in adaptation and personalization approaches that use artificial intelligence. Bringing together methods, techniques and experiences from these research areas is the motivation of PALE this year at AIED. Its aim is to share and discuss the new trends in current research, with specific focus on how current research on artificial intelligence combined with data science and other disciplines can support designers and developers to improve learning in its different stages. The purpose is to give and share promising ideas on approaches that cater for the increasing amount of information available from immediate (e.g., in terms of wearable devices) to broader contexts in order to provide personalized learning assistance bridging the behavioral and the computational. In particular, this eighth edition of PALE workshop includes 6 papers dealing with detecting reading strategies, providing personalized scaffolding to support student learning of written argumentation, using digital avatars who resemble learners to investigate their impact on learning, evaluating the learning effectiveness of a recommender system, comparing the performance of a proposed eye-gaze feature classification method, and providing instructors with visualized information on sentiment and affective state of their students.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>CCS CONCEPTS</title>
      <p>•Applied computing →</p>
      <sec id="sec-1-1">
        <title>Education</title>
        <p>→ Interactive learning
environments; • Information Systems → World Wide Web ➝
•</p>
      </sec>
      <sec id="sec-1-2">
        <title>Users and interactive retrieval</title>
        <p>➝</p>
        <sec id="sec-1-2-1">
          <title>Personalization Personalization</title>
          <p>1</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>INTRODUCTION</title>
      <p>
        The 8th edition of the International Workshop on
Personalization Approaches in Learning Environments (PALE)
took place on June 30th, 2018 and was held in conjunction with the
19th International Conference on Artificial Intelli
        <xref ref-type="bibr" rid="ref3">gence in
Education (AIED 2018</xref>
        ). This workshop is a follow-up of seven
previous editions. The focus of this workshop series is put on the
different and complementary perspectives in which personalization
can be addressed in learning environments (e.g., informal,
workplace, lifelong, mobile, contextualized, and self-regulated
learning). Previous editions addressed several important topics in
this field, such as behavior and embodiment of pedagogic agents,
suitable support of self-regulated learning, appropriate balance
between learner control and expert guidance, design of personal
learning environments, contextual recommendations at various
levels of the learning process, tracking of and reaction to affective
states of learners, harmonization of educational and technological
standards, big data processing for learning purposes, predicting
student outcomes, adaptive learning assessment, and evaluation of
personalized learning systems.
      </p>
      <p>From the past experience we have identified new areas of
interest in this research scope to complement the previous ones.
Thus, in this workshop edition we aim at sharing and discussing the
new trends in current research on how user modeling and associated
artificial intelligent techniques are able to contextualize and
manage the increasing amount of information coming from the task
at hand and its surrounding environment in order to provide the
personalization support in a wide range of learning environments,
which are increasingly more sensitive to the learners and their
context. This covers many interrelated fields such as: intelligent
tutoring systems, learning management systems, personal learning
environments, serious games, agent-based learning environments,
and others. Furthermore, we aim to cover the demanding need of
personalized learning in wider contexts ranging from daily life
activities to massive open online courses (MOOCs). Thus, PALE
offers an opportunity to present and discuss a wide spectrum of
issues and solutions.</p>
      <p>Following the experience from previous editions of this and
related workshops, PALE combines the classic 'mini-conferences'
approach with working group meetings around a specific problem.
It follows the Learning Cafe methodology to promote discussions
on some of the open issues coming from the presented papers. Each
Learning Cafe consists of brief presentations of the key questions
posed and small group discussions with participants randomly
grouped at tables. Each table is moderated by one expert in the topic
under discussion (mostly the presenter of the paper who has
addressed the issue) and participants change tables during the
discussion with the aim to share ideas among the groups.</p>
      <p>
        What follows is a
        <xref ref-type="bibr" rid="ref4 ref5">n introduction of PALE 2018</xref>
        motivation and
themes as well as an overview of the contributions accepted and
discussed in the workshop.
2
      </p>
    </sec>
    <sec id="sec-3">
      <title>MOTIVATION</title>
      <p>
        PALE 2018 is focused on enhancing sensitivity towards the
management of big educational data coming from learners'
interactions (e.g., multimodal sensor detection of attention and
affect) and technological deployment (including web, mobiles,
tablets, tabletops), and how can this wide range of situations and
features impact on modeling the learner interaction and context. In
the current state of the art it is not clear how the new information
sources are to be managed and combined in order to enhance
interaction in a way that positively impacts on the learning process
whose nature is essentially adaptive. Thus, this editio
        <xref ref-type="bibr" rid="ref4 ref5">n of PALE at
AIED 2018</xref>
        aims to give and share promising ideas to the research
question: "Which approaches can be followed to cater for the
increasing amount of information available from immediate (e.g.,
in terms of wearable devices) to broader contexts in order to
provide effective and personalized assistance in learning situations
bridging the behavioral and the computational?" Thus, it captures
current trends of the research fields of AIED, learning sciences,
learning analytics as well as multimodal interaction research in
HCI.
      </p>
      <p>The AIED session of PALE includes (but is not limited to) the
following topics:</p>
      <sec id="sec-3-1">
        <title>User engagement in learning processes</title>
        <p>Data processing within and across learning situations
Ambient intelligence</p>
        <p>Learner and context awareness




</p>
      </sec>
      <sec id="sec-3-2">
        <title>Cognitive and meta-cognitive scaffolding</title>
        <p>Cognitive and meta-cognitive scaffolding
Adaptive mobile learning
Wearable devices for sensing and acting in ubiquitous
learning scenarios</p>
        <p>Tracking technologies for accessible learning for all
3</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>CONTRIBUTIONS</title>
      <p>A peer-reviewed process was carried out to select the workshop
papers. At least three members of the Program Committee with
expertise in the area reviewed each paper. As a result, 6
submissions were accepted (out of 7), which discuss ideas and
progress on several interesting topics, such as detecting reading
strategies, providing personalized scaffolding to support student
learning of written argumentation, using digital avatars who
resemble learners to investigate their impact on learning, evaluating
the learning effectiveness of a recommender system, comparing the
performance of a proposed eye-gaze feature classification method,
and providing instructors with visualized information on sentiment
and affective state of their students. All these works specially focus
on the enhanced sensitivity towards the management of educational
data coming from multimodal learners' interactions and
technological deployment, and how can this wide range of
situations and features impact on modeling the learner interaction
and context.</p>
      <p>In particular, there are four contributions that deal with
multimodal input data.</p>
      <p>Kachergis et al. [2] describe a supervised machine learning
based system aimed at detecting reading strategies in task-oriented
readings. Three relevant reading strategies features were detected
(the ratio of sentences that readers skimmed too quickly, the
number of unique sentences read, and the variance of time spent
reading each sentence). These features are easy to automatically
extract in tablet based reading and differ from typical process
variables used to study task oriented reading. The study involved
44 fourth-year vocational secondary training students and 1091
graphs of students’ behavior recorded on tablets, which were
classified by human coders. These ratings were used to train a
classifier (eXtreme Gradient Boosting) on 13 features extracted
from the students’ reading behavior. The overall accuracy for
classifying reading strategies was 0.74, significantly greater than
chance. Searched reading strategies were the easiest to identify,
with a balanced accuracy of 0.84, followed by intensive (0.81) and
targeted reading strategies (0.69). However, both human coders and
the classifier had difficulty identifying targeted reading, suggesting
a need for further research.</p>
      <p>Elouazizi et al. [3] report a pilot study on the use of the
MindWare software, which offers personalized scaffolding to
support student learning of written argumentation. This system is
equipped with Natural Language Processing and Machine Learning
modules that analyze and weigh the usage of the components of an
argumentation voice, viz., the balanced use of stancing, hedging,
logical connections, and coherence. MindWare is used to scaffold
the metacognitive processes that underlie learning aspects of
Workshop Preface
written argumentation in the context of science education. To this
it provides, in terms of dashboards, scaffolding and formative
feedback (in visual and numerical form) to the learner and the
performance of a particular student, and/or those of groups of
students to the instructors. Preliminary results from a small-scale
pilot show that meta-cognitive scaffolding strategies have
contributed to increasing the levels of the learners’ confidence in
appreciating and using the components of the argumentation voice
in their written essays. From the study follows that it is required
further analysis on both (1) how the components of the
argumentation voice have evolved or devolved across the drafts of
the essays the students have submitted to MindWare, and (2) the
significance, if any, of the changes in the grades of the students.</p>
      <p>Parikh and Kalva [6] present a paper that focuses on comparing
the performance of an eye-gaze feature classification method
proposed by the authors (FWLC, a non-probabilistic statistical
feature weighted linguistic classifier) with five popular classifiers.
The ultimate purpose is to detect learning difficulty during a
learning exercise and adapt content. More specifically, learning
difficulty is defined here in terms of the novelty of words in written
text. This is reflected in the classification process, which “classifies
into two level of learning: a novel (positive class) or a familiar
(negative class)". From a preliminary small-scale case study
involving eight students, results show that the given method (in its
three versions) provides better True Positive Rates (TPR) for novel
words than the five machine learning classifiers. However, the
mean prediction accuracy of the best classifier is 6,6% higher than
the best version of FWLC. From this study, follows that both the
method and its usage needs further research.</p>
      <p>The work described in Schubert et al [7] provides instructors
with visualized information on the sentiment and affective state of
their students and allows them to examine how the students'
sentiment and emotional state change over the duration of a course.
The approach is aimed at showing to the instructor both the
sentiment of the overall group of students and the emotional state
and personality features of an individual student. The ultimate
purpose here is to leverage the combination of these approaches in
order to enable instructors to know how a very large body of
students are perceiving the work to be performed as well as
personalize intervention techniques based on the situation an
individual is facing. However, the approach, which uses Microsoft
Text Analytics API (for sentiment extraction) and IBM Watson
Tone Analyzer (for detection of emotional state and personality
profile) was not used for actual interventions yet. The paper
concludes pointing to further research on scoring text based on
several factors including the subject domain, weighting and
managing posts and tracking interventions to trigger and refining
appropriate actions.</p>
      <p>The other two papers propose a technological deployment.</p>
      <p>Wang et al. [4] discuss the design and evaluation of a digital
doppelganger as a virtual human listener in a
learning-byexplaining paradigm. Digital doppelgangers are virtual humans that
highly resemble the real self but behave independently. The paper
investigates how the increasing similarity of the physical
appearance between the agent (built with Rapid Avatar Capture and
Simulation: RACAS) and the student may impact on their learning.
The analysis and results from a preliminary study involving 41
students focused on their perceptions while interacting with both a
doppelganger avatar and a virtual human (with photorealistic
appearance, not based on any resemblance to the participant), offer
some clues into the possibilities and limitations of the application
of this technology to build pedagogical agents. The paper did not
find any significantly statistical result over different hypothesis but
found some evidence on a possible trend that personalizing a
pedagogical agent’s appearance to be similar to the student’s
physical appearance may play a role in the efficacy of pedagogical
agents. Still, this issue needs to be further investigated.</p>
      <p>Dang and Ghergulescu [5] focus on evaluating the learning
effectiveness of a recommender system (powered by Adaptemy's
AI Engine) in terms of average lesson success rate and
improvement per lesson. The data used in this analysis comes from
4257 students and 80266 learning lessons in a Math course. Three
main cases with different levels of teachers’ guidance are studied.
In the first case the system makes recommendations with no input
from the teacher, in the second recommendations are
looselyguided by teacher input through assignment in a topic, and in the
third there are no system recommendations but lessons specified by
teachers. The centre of the recommendation is the specific concept
to work with. In each case the results are compared between the
lessons done on system-recommended concepts and the lessons
done on other concepts. The results indicated that both the learning
success-rate and the improvement per lesson are higher if the
system-based recommendations are followed, in all the three cases.
According to this study, choosing the right difficulty levels of
concepts to be worked on is part of the reason why working on the
concepts recommended by the engine would gain higher
improvement per lesson.
4</p>
    </sec>
    <sec id="sec-5">
      <title>CONCLUSIONS</title>
      <p>The current edition of the PALE workshop deals with several
interesting issues: detecting reading strategies in task-oriented
readings, personalized scaffolding to support student learning of
written argumentation, investigating how the increasing similarity
of the physical appearance between the agent (a digital
doppelganger) and the student may impact on a
learning-byexplaining paradigm, evaluating the learning effectiveness of a
recommender system in terms of average lesson success rate and
improvement per lesson, comparing the performance of a proposed
eye-gaze feature classification method with five popular classifiers,
and providing instructors with visualized information relating to the
sentiment and affective state of their students and allow them to
examine how the students' sentiment and emotional state changes
over the duration of a course.
5</p>
    </sec>
    <sec id="sec-6">
      <title>ACKNOWLEDGEMENTS</title>
      <p>PALE chairs would like to thank the authors for their submissions
and the AIED workshop chairs for their advice and guidance during
the PALE workshop organization. Moreover, we also would like to</p>
      <p>
        The or
        <xref ref-type="bibr" rid="ref3">ganization of the PALE 2018</xref>
        workshop has been partially
supported by the following projects: BIG-AFF – Fusing
multimodal Big Data to provide low-intrusive AFFective and
cognitive support in learning contexts (TIN2014-59641-C2-2-P)
and Supervised Educational Recommender System (VEGA
1/0475/14), HIBER: Human Information Behavior in the Digital
Space (APVV-15-0508) and ADAPTION: Migration zum
Cyberphysischen Produktionssystem (BMBF 02P14B023).
      </p>
    </sec>
  </body>
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