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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Automatic Approach for Comparison of Study Programmes</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Alla Anohina-Naumeca</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ilze Andersone</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Zohra Bellahsene</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Remi Coletta</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vita Graudina</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Janis Grundspenkis</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Duy Hoa Ngo</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Riga Technical University</institution>
          ,
          <addr-line>Riga</addr-line>
          ,
          <country country="LV">Latvia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Université Montpellier 2, LIRMM</institution>
          ,
          <addr-line>Montpellier</addr-line>
          ,
          <country country="FR">France</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper presents an approach for comparing study programmes in automatic way by using two software tools: (i) the IKAS system allowing construction of concepts maps representing curricula and their transformation into ontologies and (ii) the WebSmatch tool allowing matching of the ontologies and providing visualization of comparison results. The results of our experiment on a real dataset of study programmes in some European universities show the effectiveness of the approach.</p>
      </abstract>
      <kwd-group>
        <kwd>concept map</kwd>
        <kwd>ontology</kwd>
        <kwd>ontology matching</kwd>
        <kwd>study programmes comparison</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Open and dynamic European educational area demands modern curricula, wide
opportunities for student mobility, and corresponding academic recognition. However,
in order to promote constructive and continuous improvements of study programmes
across the Europe and to harmonize them with requirements of the labour market, as
well as to identify possibilities for student mobility it is necessary to develop tools for
comparison of curricula. It is obvious that such tools must be based on some kind of
curriculum mapping. The mapping process represents spatially the different
components of the curriculum so that the whole picture and the relations and connections
between the parts are easily seen [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Results of comparison can be used in various
ways, for example, for identification of possibilities for student mobility or lifelong
education, creation of joint programmes, accreditation of new study programmes, etc.
      </p>
      <p>
        The paper presents an approach for comparison of study programmes on the basis
of concept maps and ontologies. Concept maps allow visualization of the structure of
a study programme and facilitation of its perceiving by non-technical users, such as
students looking for possibilities of mobility. Concept maps are constructed and then
transformed into ontologies by using the IKAS tool [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], which provides a graphical
interface for manipulation of concept maps. Ontologies are used as an input for the
matching tool WebSmatch [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] which compares study programmes and displays
results. The main contributions of this paper are: (i) representation of study programmes
by means of concept maps; (ii) an algorithm for transformation of concept maps into
ontologies; (iii) an approach for comparison of study programmes by matching of the
corresponding ontologies and visualization of the results in the form of clusters.
      </p>
      <p>The paper is organized as follows. Section 2 describes how to create a concept map
for a study programme. Section 3 gives an overview of the approach and describes the
techniques used for curricula matching. Results of matching are reported in Section 4.
Related works are presented in Section 5. Finally, Section 6 contains the conclusion.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Concept Map Based Representation of Study Programmes</title>
      <p>
        Concept mapping is a pedagogical tool developed by Novak in 1970s [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] with the aim
to facilitate student learning by presenting key concepts in a knowledge domain and
relations between them in a graphical way. A concept map is a knowledge
representation tool visualized by a graph consisting of finite, non-empty set of labelled nodes,
which depict concepts, and finite, non-empty set of arcs (directed or undirected),
which express relations between pairs of concepts. Linking phrases can specify kinds
of relations between concepts. A proposition (concept-relation-concept triple) is a
semantic unit of concept maps. It is a meaningful statement about some object or
event in a problem domain [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Due to hierarchical nature of the structure of study
programmes, the concept map of a curriculum can be divided into several levels:
 1st-General level. It can consist at least of four main nodes. Three of them represent
the name of the educational institution, the name of the structural unit
implementing the study programme, and the title of the study programme. The last one
labelled “Study programme” serves as a starting point for comparison process of two
study programmes. Moreover, it is possible to add more nodes representing
educational institutions or structural units if the study programme is joint by its nature;
 2nd-Level of study years presents duration of the study programme;
 3rd-Level of semesters displays incorporation of particular semesters into study
years;
 4th-Level of major field. Sometimes study programmes, after mastering of some
general courses, allow students to choose a particular major field, for example,
software design, computer networks, and so on. Each major field typically includes
different study courses;
 5th-Level of course groups presents grouping of courses on the basis of students'
freedom degree to choose them for studying. Examples of groups are compulsory
courses, free electives, restricted electives, and so on;
 6th-Level of course titles displays particular courses included in the programme;
 7th-Level of course topics presents specific topics forming a particular course;
 8th-Level of concept maps of particular topics.
      </p>
      <p>The described structure of a concept map for a study programme is shown in
Figure 1. Here, the macro map is provided by levels starting from the general level and
finishing with the level of course topics. In their turn, concept maps of particular
topics represent micro maps.</p>
      <p>It is necessary to note that for presentation of a specific study programme some
levels can be omitted if the description of the curriculum is not complete or some
concepts are not applicable at all, for example, major field. In order to be able to
perform comparison of curricula at least at a shallow level, three levels must be
presented: general level, study years, and course titles.</p>
      <p>Unit</p>
      <p>Part of</p>
      <p>The main linking phrase for relations between nodes at different levels is “part of”
representing integration of particular parts into a whole: topics into courses, courses
into groups of courses. Unique is the linking phrase “title” between the node “Study
programme” and the node displaying the title of the study programme and the linking
phrase “is implemented by” between “Study programme” and “Unit”. At the levels of
course titles and topics, the linking phrase “is a prerequisite” can be added to relations
to show that one course/topic must be learnt before the other one or, in other words,
knowledge from one course/topic are essential for understanding of the other
course/topic. At the eighth level, relations between nodes can be presented by any
linking phrases because concepts of particular topics can be related in a variety of
ways using not only standard linking phrases such as “is a”, “part of”, “has a value”,
but also any linguistic phrases.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Comparison of Study Programmes</title>
      <p>
        Figure 2 displays the proposed approach for comparison of study programmes using
concept maps and ontologies. First of all, on the basis of the acquired descriptions of
curricula, concept maps are constructed using the IKAS system [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The system
provides a graphical interface for manipulation of concept maps. Secondly, using the
same system, the concept maps are transformed into ontologies. After that, to perform
the comparison or, in other words, the matching between the resulting ontologies and
to acquire clustering view, the matching tool WebSmatch [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] is used.
Correspondence between elements of the concept map and main elements/entities of
OWL ontology is shown in Figure 3. A concept in a concept map can correspond to a
class, an instance, a data type property and its value in the OWL ontology depending
on a linking phrase which specifies a relation between two concepts. The linguistic
and “part of” linking phrases agree to the object property. The algorithm for
transformation of a concept map into an ontology consists of seven steps [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] during which all
elements of the concept map are handled to determine their correspondence to
ontology elements. As a result, the appropriate ontology is constructed.
Different techniques are used for discovering semantic mappings between ontologies
representing study programmes. Each of them corresponds to an individual matcher
that implements a single matching algorithm. Next, machine learning techniques are
applied to combine individual matchers. Element- and structure-level approaches are
distinguished. The element-level approaches exploit information used to describe
entities such as ID, label, and description:
 For ID matching, string and linguistic metrics are utilized to calculate similarity
score between two IDs;
 For label matching (chain of words separated by blank spaces), the WebSmatch
includes several linguistic metrics;
 For description matching, a profile for each entity in the ontology is constructed by
gathering descriptive information of its related entities. A profile is viewed as a
vector of weights of terms. Similarity of two entities is calculated by cosine
measure of two vectors corresponding to entities’ profiles in the vector space model.
The structure-level approaches exploit information about relations between entities.
Methods which are used rely on the intuition that elements of two distinct ontologies
are similar when their adjacent elements are similar [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. These criteria are all
developed and used as structure-level individual matchers in the WebSmatch tool.
3.3
      </p>
      <p>
        Clustering Similar Study Programmes
Based on semantic mappings that were previously discovered between ontologies, the
WebSmatch tool [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] automatically clusters the set of related documents (ontologies).
The clustering process works as follows. First, it computes a distance between each
pair of documents. More technically, a bipartite graph is built, where nodes from the
left side are the attributes (metadata) of the first document, nodes from the right side
are the attributes (metadata) of the second document, and edges are the matches
between concepts. The weights over edges are the confidence values of the discovered
matches. From this weighted bipartite graph, the maximum matching is computed.
Then, this number is normalized by dividing this maximum matching by the
minimum numbers of attributes between the first and the second document. From these
distances between documents, a minimum energy graph model (adapted from [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]) is
built, which represents the cluster structure based on repulsion between documents.
4
      </p>
    </sec>
    <sec id="sec-4">
      <title>Experimental Results</title>
      <p>To check the feasibility of our approach, an experiment was conducted over a corpus
of sixteen variations of seven study programmes of five European universities (see
Table 1). Figure 4 illustrates the result of the clustering service. There are five
different clusters. Study programmes (ontologies) are in the same cluster if and only if they
share some semantics links. Study programmes in the clusters have different
diameters: the larger is the diameter, the more representative of the cluster is the study
programme. Therefore, the largest diameter corresponds to the programme which is more
related to other study programmes. The variations of the same programme differ only
by few courses of restricted electives taken by students and/or information about
learning outcomes. For example, in one variation of UR and RTU Business
Informatics programmes the course descriptions are supplemented with learning outcomes. It
is therefore not surprising that all of RTU Business Informatics programme variations
are considered similar and are included in the first cluster.</p>
      <p>There is one exception. RTU Computer Systems programme with all restricted
electives courses is included in the fourth cluster together with RTU Information
Technology and UTCluj Computer Science study programmes. There is a strong
similarity between the structure and content of UTCluj study programme and both
mentioned study programmes of RTU, which are essentially the same programme during
the first two study years. The similarity between these three programmes is evident;
however, it would be logical to cluster them together.</p>
      <p>The fifth cluster is formed by the study programmes of UV and UL. There are
some analogous courses between the mentioned programmes, however, actual
similarity between UV and RTU Bachelor study programmes is more pronounced both
structure- and content-wise.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Related Work</title>
      <p>
        A number of concept map application outside learning have been already explored;
inter alia curriculum planning and organization. According to [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], in curriculum
planning it is necessary to construct a global macro map showing the major ideas planned
to present in the whole course, or in a whole curriculum, and also more specific micro
maps to show the knowledge structure for a very specific segment of the instructional
program. In this direction, there are research studies concerning not only structuring
of curricula, but also analyzing relationships between subjects and competences [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]
and alignment of a local curriculum with state standards [18]. However, the
comparison of study programmes on the basis of concept maps seems a quite new field,
because no corresponding publications have been found.
      </p>
      <p>
        Traditionally, in the context of curricula, ontologies have been used for
competence categorization [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], categorization and description of knowledge used in
different study programmes [
        <xref ref-type="bibr" rid="ref11 ref12">11-12</xref>
        ], construction of a study course and learning path, for
example, [
        <xref ref-type="bibr" rid="ref13 ref14">13-14</xref>
        ]. Despite this quite wide use of ontologies in area of curricula and
number of research in the field of ontology comparison, matching, and alignment [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ],
there is no evidence that ontologies have been applied for comparison of study
programmes. Moreover, taking into account progress in development of advanced
ontology matching tools, transformation of concept maps (which do not have such tools,
but provide intuitive visualization of a problem domain) into ontologies is important
in order to use ontology matching tools and methods for matching concept maps.
Therefore, combination of ontology and concept map similarity [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] and already
existing number of studies in ontology comparison makes background for research in this
paper.
6
      </p>
    </sec>
    <sec id="sec-6">
      <title>Conclusion</title>
      <p>In this paper, we have proposed an approach that is aimed to perform comparison of
study programmes in automatic way by using a matching tool. The approach consists
of representing study programmes as concept maps and their further transformation
into ontologies. Concept maps are chosen as the main instrument for visualization of
the structure of a curriculum as they include only labelled nodes and relations and
facilitate perceiving the structure of the curriculum by non-technical users who are
interested in comparison of study programmes. The approach is supported by two
software tools: the IKAS system allowing construction and transformation of
concepts maps and the matching tool WebSmatch performing matching of ontologies
received from concept maps and providing the clustering service. The clustering helps
to make results of matching more demonstrative and easier understandable. The
results provided by the experiment are very promising and allow believing that this
work is one step towards the support of student mobility.</p>
    </sec>
  </body>
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</article>