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      <title-group>
        <article-title>MoocRec.com : Massive Open Online Courses Recommender System</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Panagiotis Symeonidis</string-name>
          <email>psymeon@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dimitrios Malakoudis</string-name>
          <email>dmalakoudis@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Informatics, Aristotle University</institution>
          ,
          <addr-line>Thessaloniki, 54124</addr-line>
          ,
          <country country="GR">Greece</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Massive open online courses (MOOCs) have recently gained a huge users' attention on the Web. They are considered as a highly promising form of teaching from leading universities such as Stanford and Berkeley. MoocRec.com is a web site that recommends courses to users so that, they can acquire those skills, that are expected from their ideal job posting. MoocRec's recommendation engine is based on Matrix Factorization (MF) model combined with Collaborative Filtering (CF) algorithm, which exploits information from external resources (i.e., users' skills, courses' characteristics, etc.) to predict course trends and to perform rating predictions according to them.</p>
      </abstract>
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  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>Massive Open Online Courses (MOOCs) platforms o er
thousands of di erent courses and each course's
registration/enrolment can be in the hundreds of thousand students.
It would be very useful, if someone could be recommended
a course to acquire those skills, that are expected from his
ideal job description.</p>
      <p>MoocRec.com is a web site that provides to users
recommendations of MOOCs. Firstly, users provide some
information about their studies and their dream job. Then,
MoocRec.com recommends to them related courses, to
acquire the required skills for getting their dream job. The
heart of the recommendation engine of MoocRec.com is
matrix decomposition over a user-course rating matrix R to
reduce its dimensions and remove noise from data. To do this,
we preserve a small number of k latent features (i.e.,
dimensions) with the objective to reveal the mainstream users'
preferences. For example, in Figure 1, we plot users and
courses, assuming that k has been tuned to 2.</p>
      <p>As shown in Figure 1, courses/users that are placed in
close distance, are the most suitable/similar to each other.
As shown, women prefer literature courses, whereas men
choose the technical ones. Speci cally, the course \English
Grammar and Style" can be recommended to Maria and
Irene, whereas \From Java to Android" course is more
suitable to John. Please notice that matrix decomposition has
also revealed a second separation, which takes place among
people's preference, towards practical and theoretical types
of courses. In MoocRec.com, we predict users' ratings over
courses based on matrix factorization (MF) technique, which
exploits information from several external
resources/matrices.</p>
      <p>The rest of this paper is organized as follows. Section 2
summarizes the related work, Section 3 summarizes the
system's architecture. Section 4 describes our recommendation
engine. Finally, Section 5 concludes this paper.
2.</p>
    </sec>
    <sec id="sec-2">
      <title>RELATED WORK</title>
      <p>
        Furnas et al. [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] proposed Singular Value Decomposition
(SVD) in Information Retrieval research eld. More
specifically, SVD captures latent associations between the terms
and the documents. SVD is a well-known factorization
technique that factors a matrix into three matrices. An instance
of SVD, known as UV-decomposition, searches for two
matrices (U and V ), whose their multiplication gives an
approximation of the original matrix R. A signi cant improvement
on the prediction accuracy of classic MF algorithm may be
obtained through the incorporation of implicit feedback into
the MF model [
        <xref ref-type="bibr" rid="ref2 ref3 ref4">2, 3, 4</xref>
        ].
      </p>
      <p>
        Extensions of classic MF algorithm have been successfully
applied for recommendations in MOOC domain to address
the problem of high students' drop-out rates from online
courses. To reduce the high students' drop-out rates, they
provide recommendations of useful forum threads to
students based on their blog history inside a MOOC discussion
forum. For instance, Yang et al. [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] have designed a latent
feature model to describe student behaviors inside a MOOC
forum.
      </p>
      <p>MoocRec.com integrates a search engine for MOOCs that
are automatically retrieved using web content mining
techniques from MOOC providers such as edX and Coursera.
It also incorporates a MOOC recommender system, which
provides a target user with personalized content according
to the skills he wishes to acquire. Therefore, we use
contentbased ltering in order to connect course's description with
the desired skills. We also embed the matrix factorization
technique and recommend MOOCs to a target user based
on previous choices of other users.</p>
      <p>Moreover, using alerts a registered user may be noti ed
of MOOCs when they become available. He may also rate
courses either explicitly or implicitly (log history). That is,
our monitoring system records the user's actions and helps
in constructing his pro le.</p>
      <p>The web crawler scans edX and Coursera web sites and
enters all the MOOCs found in a MySQL database, In
addition, an additional web crawler mines from LinkedIn the
skills which are connected to the top-rated jobs. Therefore,
the database holds information that correlates jobs to skills
and skills to courses, which makes course and job
recommendation possible.</p>
    </sec>
    <sec id="sec-3">
      <title>RECOMMENDATION ENGINE</title>
      <p>Figure 3 illustrates an example of the course
recommendations which are provided by our system. An important
characteristic of our recommendations is that the user is
informed about the reason he was recommended a course. For
example, course \Data Analysis for Life Sciences 6:
Highperformance Computing for Reproducible Genomics" is
recommended because it is related to Life Sciences and
Genomics. Our recommendation algorithm, places rst the
courses which provide the greatest number of skills to the
target user. Moreover, courses that start soon or are
selfpaced have priority towards others.
5.</p>
    </sec>
    <sec id="sec-4">
      <title>CONCLUSIONS</title>
      <p>In this paper, we proposed MoocRec.com, which exploits
information from external resources (i.e., users' skills, courses'
characteristics, etc.) to provide course recommendations. In
future, we want to test experimentally our system to check
its accuracy e ectiveness in terms of accurate
recommendations.</p>
    </sec>
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  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>G.</given-names>
            <surname>Furnas</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Deerwester</surname>
          </string-name>
          , and S. et al. Dumais.
          <article-title>Information retrieval using a singular value decomposition model of latent semantic structure</article-title>
          .
          <source>In Proc. ACM SIGIR Conf.</source>
          , pages
          <volume>465</volume>
          {
          <fpage>480</fpage>
          ,
          <year>1988</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>Yehuda</given-names>
            <surname>Koren</surname>
          </string-name>
          .
          <article-title>Factorization meets the neighborhood: a multifaceted collaborative ltering model</article-title>
          .
          <source>In Proceeding of the 14th ACM SIGKDD international conference on Knowledge discovery and data mining</source>
          , pages
          <volume>426</volume>
          {
          <fpage>434</fpage>
          . ACM,
          <year>2008</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>Yehuda</given-names>
            <surname>Koren and Robert M. Bell</surname>
          </string-name>
          .
          <article-title>Advances in Collaborative Filtering</article-title>
          . In Francesco Ricci, Lior Rokach, Bracha Shapira, and Paul B. Kantor, editors,
          <source>Recommender Systems Handbook</source>
          , pages
          <volume>145</volume>
          {
          <fpage>186</fpage>
          . Springer,
          <year>2011</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <given-names>Arkadiusz</given-names>
            <surname>Paterek</surname>
          </string-name>
          .
          <article-title>Improving regularized singular value decomposition for collaborative ltering</article-title>
          .
          <source>In Proceedings of KDD cup and workshop</source>
          , volume
          <volume>2007</volume>
          , pages
          <issue>5{8</issue>
          ,
          <year>2007</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <given-names>Diyi</given-names>
            <surname>Yang</surname>
          </string-name>
          , Mario Piergallini, Iris Howley, and
          <string-name>
            <given-names>Carolyn</given-names>
            <surname>Rose</surname>
          </string-name>
          .
          <article-title>Forum thread recommendation for massive open online courses</article-title>
          .
          <source>In Proceedings of 7th International Conference on Educational Data Mining</source>
          ,
          <year>2014</year>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>