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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Analyzing the relationships between learning analytics, educational data mining and AI for education</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Hugues Labarthe</string-name>
          <email>hugues.labarthe@ac-creteil.fr</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vanda Luengo</string-name>
          <email>vanda.luengo@lip6.fr</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>François Bouchet</string-name>
          <email>francois.bouchet@lip6.fr</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Incubateur Académique, Rectorat de Créteil</institution>
          ,
          <addr-line>94700 Créteil</addr-line>
          ,
          <country country="FR">France</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Sorbonne Université</institution>
          ,
          <addr-line>CNRS</addr-line>
          ,
          <institution>Laboratoire d'Informatique de Paris 6</institution>
          ,
          <addr-line>LIP6, 75005 Paris</addr-line>
          ,
          <country country="FR">France</country>
        </aff>
      </contrib-group>
      <fpage>63</fpage>
      <lpage>72</lpage>
      <abstract>
        <p>Baker and Siemens have well explained the theoretical differences and similarities between the educational data mining (EDM) and learning analytics (LA) communities in their 2012 seminal paper, in which they also wished for bridging the gap between both communities. Moreover, since its creation as an independent conference in 2009, EDM has been evolving in parallel with the intelligent tutoring systems (ITS) / artificial intelligence for education (AIED) community. But what are the actual links that exist between these three communities in terms of members and research topics: to what extent do they overlap and work together? Are they getting closer from each other or drifting apart? Is each community specific to researchers with different backgrounds, modeling and analysis techniques? Those are some of the questions we investigate using a quantitative analysis led between 2007 and 2017 through: a social network analysis of the 3 communities, involving the 1822 scientists who participated in program committees and/or appeared as authors of the associated journals (IJAIED, JEDM and JLA); and a text analysis of abstracts of articles published in these journals. Results reveal the clear differences between these communities, their topics, practices and research methods.</p>
      </abstract>
      <kwd-group>
        <kwd>learning analytics</kwd>
        <kwd>educational data mining</kwd>
        <kwd>artificial intelligence in education</kwd>
        <kwd>social network analysis</kwd>
        <kwd>text analysis</kwd>
        <kwd>communities</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>At the beginning of the 2010s, two communities progressively structured themselves
to study learning data: the Society for Learning Analytics Research (SoLAR) and the
International Educational Data Mining Society (IEDMS). In the meantime, the
International AIED Society, gathered around the encompassing “Artificial Intelligence for
EDucation” (AIED) theme, also started to analyze more and more data coming for their
systems (in particular, intelligent tutors). Thus, three research communities have been
tackling similar issues, and there has now been enough history for a data-based
approach (valued by all three communities) to examine what distinguishes them and what
brings them together.</p>
      <p>
        The theme of Educational Data Mining first appeared during the ITS (Intelligent
Tutor Systems) conference in Montreal in 2000 [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. But it is really in 2005, with the
first workshop on EDM held in Pittsburgh in conjunction with the AAAI (Association
for the Advancement of Artificial Intelligence) conference that the theme started to take
off. Most of the research work presented at that time were led on data coming from ITS
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The first state of the art work was published in 2007 by Romero et Ventura [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], and
was followed by the creation of the yearly EDM conference in 2008, and of its
associated journal, the Journal of Educational Data Mining (JEDM), in 2009. In parallel, and
independently, the Society for Learning Analytics Research (SoLAR) was founded in
2011 with its associated yearly conference, LAK (Learning Analytics and Knowledge),
followed in 2014 by its own journal, the Journal of Learning Analytics (JLA). Finally,
the AIED community has been structured for three decades around two alternating
biyearly conferences, AIED (Artificial Intelligence for Education), which became yearly
in 2017, and ITS (Intelligent Tutoring Systems), as well as a journal, IJAIED
(International Journal of Artificial Intelligence for Education).
      </p>
      <p>
        Very early on, the two new communities have acknowledged each other and the
differences that exist between them, mainly in the background of its lead members
(semantic web for LA, educational software for EDM), the analysis techniques they mostly
use (social network analysis for LA, more machine learning for EDM), and their overall
goal (empowering learners and teachers while leaving them in charge for LA,
automated adaptation by the computer for EDM). Those key differences are well
summarized in [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], in which the authors also call for joining the forces of the two communities
to build upon each other’s strengths. Although the interactions have been happening
[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], both communities have also kept their respective identities [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], which have been
established through publications to federate their respective domains [
        <xref ref-type="bibr" rid="ref7 ref8 ref9">7–9</xref>
        ].
      </p>
      <p>Overall, a decade after the first EDM conference, and three after the first ITS, the
three communities are thriving, and we can wonder about the relationships between
each other and their respective impact on education. We decided to study three types of
data: (1) the reviewers for the conferences associated to each community (AIED/ITS,
EDM, LAK); (2) the authors of the papers published in the journals associated to each
community (IJAIED, JEDM, JLA); (3) the abstracts of the papers published in the
journals associated to each community. Using these datasets, we performed exploratory
analyses of the overlap of the communities as well as of their individual specificities.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Data collection and cleaning</title>
      <p>For each of the aforementioned datasets, we decided to consider a period of 11 years
(2007-2017), which encompasses the whole existence of the EDM community.
Although it may appear to give an emphasis to the data from that community, the LA
community has published overall more intensively since its birth in 2011 (cf. table 1
further), and we therefore believe the 4 extra years are not affecting the validity of our
results. Regarding the AIED community, although we had access to older data, we
believed the changes in terms of popular scientific topics and approaches over time did
not justify including it, and that it made more sense to use a similar period of 11 years.</p>
      <p>The first dataset (reviewers) was collected mostly manually by extracting the list of
reviewers’ names included in the proceedings of each conference. We extracted the
names from PDF version of the proceedings, selecting any name listed under the
“Program Committee” and “Reviewers” sections, excluding others such as “Conference
chairs” or “Organization committee”. The choice of reviewers instead of authors was
justified by the fact that many conferences authors may appear only once, and that
authoring a single paper in a conference does not necessarily imply a tight relationship
with the associated community. Conversely, being invited to review papers for a
conference usually indicates a sustained link (including but not limited to authorship), more
relevant for a community analysis like the one we wanted to perform.</p>
      <p>The second (authors) and third (abstracts) datasets were extracted automatically
using a webcrawler tool (Scrapy) specially configured to extract from each website the
information relative to published papers (title, authors, abstract, keywords, volume,
issue, year). For IJAIED, information was extracted from both the Springer and ijaied.org
websites, but only the ijaied.org data was kept because the Springer data started in 2013
only. We excluded from these datasets articles explicitly identified as an editorial,
including guest editorials for special sections in the case of JLA, to focus only on research
papers. A tedious review of names, surnames and even positions resulted in creating a
single table, reducing a list of 4026 names to 1505 individuals. The abstracts were
analyzed using Python packages for text analysis and visualization.</p>
      <p>Overall, when not counting twice authors and reviewers who published/reviewed
more than once for a given journal/conference, we see in Table 1 that AIED remains
logically the dominant community of the three, with 687 reviewers and 386 authors. In
terms of reviewers, EDM and LA are very close from each other and are far less than
half of the reviewers for AIED. However, in terms of journal authors, despite a later
start, the LA community has published almost 2.5 times more articles than the EDM
one, with almost twice more individual authors.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Conference reviewers community analysis</title>
      <p>First, we focus on the conference reviewers’ dataset to analyze the evolution of the
reviewers’ network among the three communities from 2007 to 2017. In a decade, the
number of scientists reviewing for each year conferences’ papers has increased by
103%, reaching 415 reviewers in 2017, showing the significant vitality of these research
fields (cf. Table 2). Moreover, the total number of scientists involved in these 28
conferences has increased considerably from 204 to 990 (+385%), showing that the growth
in yearly reviewers came from a community more than twice larger overall. Despite a
small drop in the number of yearly reviewers from 2008 to 2010, the number of
scientists involved in these reviews has never stopped increasing, with two peaks: +29% in
2008 for the first EDM conference and +36% in 2011 for the first LAK conference.</p>
      <p>All
EDM
LAK
Cross
conf.</p>
      <p>AIED ITS % Total</p>
      <p>Due to its anteriority in the field, we could make the hypothesis that the AIED/ITS
conferences provided most of the reviewers for the two other communities. To test this
hypothesis, we examined the overlap of reviewers between LAK/EDM and the
AIED/ITS conferences (cf. Table 3). Until 2014, the AIED community has recruited
two thirds of the reviewers, with 88 % of them exclusively dedicated to its Program
Committee. Then, it decreases to only half of the total, and 70-75% of exclusive
reviewers. It is a sign not only of the growth of the LA/EDM communities, but also of
the increased porosity with the older AIED community. As we can see in Table 3, the
two new communities have been relying upon this first one, at least at their beginning.
These communities have progressively grown from one fifth of the network together,
to one third each, with LAK having the fastest growth. The proportion of
cross-conferences’ reviewers for more than one conference has remained constant overall, at around
8-12%, with two peaks to 15% in 2010, and to 14-19% in 2015-2017.
Cross-Conf. reviewers
LAK Exclusive reviewers
EDM Exclusive reviewers
AIED Exclusive reviewers
Cumulative number of reviewers
AIED/ITS conferences have been sharing a quarter of all their reviewers (141 out of
425): it could come from the fact that those conferences have been alternating over the
period considered (odd years for AIED and even years for ITS) – although we see that
both of them also have their own subset of reviewers. But beyond this particular case,
the number of persons who really belong to two or more communities remains limited:
only 13.7% of the reviewers (136 individuals) cross-reviewed between, at least, two of
the following communities: AIED/ITS (considered as a single one), EDM and LAK.
As illustrated by Figure 2, the common core of the three communities consists of 32
reviewers. The most surprising result was to see how the LAK community was the least
related to the others, when compared with the bonds between EDM, ITS and AIED.
The reviewers common to each pair of community, as well as to the three communities
are in Table A in Appendix, and in Table 4 for a synthesis.
AIED-ITS EDM-ITS EDM-AIED LAK-ITS EDM-LAK LAK-AIED
25
20
18
14
14
10</p>
    </sec>
    <sec id="sec-4">
      <title>4. Journal authors community analysis</title>
      <p>Using the second dataset, we considered the papers published in the communities’
respective journals (IJAIED, JEDM and JLA). From 2007 to 2017, there are 996
signatures corresponding to 748 unique authors of 349 articles. 80% of these unique authors
signed 1 paper; 14% signed 2, and 6% signed at least 3 of them. Overall, the low number
of authors of more than one paper limits this analysis, but we performed the same
crossreference analysis as in the previous section for reviewers. It reveals that a dozen of
authors published in each pair of journals (cf. Table B in appendix), and 8 central
authors published in the three of them.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Textual analysis of journal abstracts</title>
      <p>Scientific communities are centered around the scientists that are part of them, but also
around some common themes. To identify the themes that are characteristics of each
community, we have tried to identify the keywords characteristics of the papers
published in the journal of each community, using the third dataset.</p>
      <p>First, we performed a cleaning of the abstracts using Python Natural Language
Toolkit (NLTK) to perform the usual first step (tokenization, lemmatization and stop
words removal). Then we used the word_cloud package to identify visually if some
keywords were appearing more in some abstracts than others (cf. Figure 3). All
communities are obviously very centered on “student”, “learning” and “usages”. The LA
and EDM communities also share the focus on data, which is missing from the AIED
community.
However, more than the similarities between the communities, we are interested in
what distinguish them from one another. To identify the keywords representative from
each community, we extracted from the compilation of the abstracts of each journal the
associated keywords using the Rapid Automatic Keywords Extraction (RAKE)
algorithm. To avoid the fact that it may overrepresent keywords cited many times by the
same article, we kept only the keywords that appeared in at least 20% of the abstracts
from each journal. We obtained a set of 110 keywords appearing in at least 29 abstracts
from IJAIED, 79 keywords appearing in at least 10 abstracts from JEDM, and 80
keywords appearing in at least 26 abstracts from JLA. Then we extracted (a) the keywords
from JEDM not appearing in JLA, (b) the keywords from JLA not appearing in JEDM,
(c) the keywords from IJAIED not appearing in JLA nor JEDM. They are summarized
in Table 5. Overall, we see that the EDM community remains very anchored in a
discovery approach (investigate, evidence, assess, understand, experiment…) when the
LA community is more in the practice (support, inform, development, act, teach…).
Although the particular techniques used in the papers do not appear with this analysis,
the focus of EDM community on a more mathematical approach (features, log, class…)
is visible, when compared to LA which focuses on “text”, “chi square” and “ratings”.
As for the AIED community, its roots in tutor systems to provide feedback while
modeling skills and knowledge from the student is also clearly visible.
JEDM
but not
JLA
large, propose, technique, behavior, group, compare, ability, educational data
mining, improve, demonstrate, ask, investigate, evidence, problem, make,
assessment, new, cover, concept, information, analyze, log, discover, apply,
assess, finding, feature, class, relate, understand, collect, experiment, task, search,
state, type
JLA but
not
JEDM
IJAIED
only
support, focus, inform, call, analytics, development, learn analytics, high, time,
n, explore, chi, rater, ever, learning, age, tool, LA, go, use, act, put, analytic,
text, teach, different, pre, end, lea, two, pose, relation
skill, tutor, instruct, evaluation, domain, interaction, interact, era, test, line,
train, know, add, view, ten, well, AI, way, feed, effective, p, prove, low,
computer, ratio, art, mode, solve, evaluate, tutor system, feedback, e tutor, effect, q,
knowledge, par, help, stem, late, differ, port, adapt, instruction, come</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion</title>
      <p>Through an analysis of the social networks of the conference reviewers and journal
authors from the AIED, EDM and LA community, we have shown that Siemens and
Baker’s call has been heard, as more and more scientists are at the frontiers between
the communities with 139 shared reviewers and 48 shared authors. The research themes
however remain clearly distinct, as shown by the keywords analysis of the journal
abstracts, with an emphasis on agents and tutors for AIED, automation and prediction for
EDM, and visualization for LA. However, these are the different pieces of the same
puzzle: enhancing learning experience through technology.</p>
      <p>This work presents some limits: we focused on 3 important communities, but which
do not represent the whole field of educational technology – extending this approach to
other communities such as the “user modeling” one, or more local communities
(ECTEL in Europe) would provide a larger overview of the domain. We could also include
conference authors and abstracts in our analysis, to see if more diversity of themes can
be identified that way. The lack of information regarding authors’ faculties for
reviewers as well as for many authors did not allow us to confirm the fact that LAK is closer
to education than the other communities. Finally, we have not considered the temporal
aspects of the network evolution over the decade, but only the final outcome.
Nonetheless, we hope that this work will contribute in structuring the communities, and
encourage more scientists to follow the trend towards more interactions between them.</p>
    </sec>
    <sec id="sec-7">
      <title>Appendix</title>
      <p>Communities</p>
      <p>Authors
Azevedo R., Boyer K. E., Chung G. K.W.K., Conati C., D'Mello S., Goldin I., Harley
J. M., Koedinger K. R., Lester J., Luckin R., Miller L. D., Nugent G., Person N., Samal
A., Soh L.-K.</p>
      <p>Blair K. P., Chin D. B., Cutumisu M., Gowda S. M, Heffernan N. T, Hoppe H. U., Kay
J., Linn M. C., Paquette L., Pardos Z., Rau M. A., San Pedro M. O. Z., Schwartz D. L.,
Segedy J. R.</p>
      <p>JEDM &amp; JLA:
11 shared</p>
    </sec>
  </body>
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</article>