=Paper= {{Paper |id=Vol-1446/smlir_submission4 |storemode=property |title=A Systematic Mapping Study on the Usage of Software Tools for Graphs within the EDM Community |pdfUrl=https://ceur-ws.org/Vol-1446/smlir_submission4.pdf |volume=Vol-1446 |dblpUrl=https://dblp.org/rec/conf/edm/IvancevicL15 }} ==A Systematic Mapping Study on the Usage of Software Tools for Graphs within the EDM Community== https://ceur-ws.org/Vol-1446/smlir_submission4.pdf
     A Systematic Mapping Study on the Usage of Software
         Tools for Graphs within the EDM Community
                      Vladimir Ivančević*                                                         Ivan Luković
   University of Novi Sad, Faculty of Technical Sciences                  University of Novi Sad, Faculty of Technical Sciences
                 Trg Dositeja Obradovića 6                                              Trg Dositeja Obradovića 6
                  21000 Novi Sad, Serbia                                                 21000 Novi Sad, Serbia
                    dragoman@uns.ac.rs                                                         ivan@uns.ac.rs



ABSTRACT                                                                  be also evidenced by the appearance of the Workshop on Graph-
The field of educational data mining (EDM) has been slowly                Based Educational Data Mining (G-EDM)1 in 2014. As a result,
expanding to embrace various graph-based approaches to                    software tools that help researchers or any other user group to
interpretation and analysis of educational data. However, there is        utilize graphs or graph-based structures (for brevity these will be
a great wealth of software tools for graph creation, visualization,       referred to as graph tools) are becoming a valuable resource for
and analysis, both general-purpose and domain-specific, which             both the G-EDM and the broader EDM community. As graphs are
may discourage EDM practitioners from finding a tool suitable for         only slowly gaining wider recognition in EDM, there could still
their graph-related problem. For this reason, we conducted a              be a lot of questions about which graph tools exist or what
systematic mapping study on the usage of software tools for               educational tasks might be supported by these tools.
graphs in the EDM domain. By analysing papers from the                    In an attempt to help EDM researchers discover more useful
proceedings of previous EDM conferences we tried to understand            information about potentially suitable graph tools, we reviewed
how and to what end graph tools were used, as well as whether             the papers presented at the past EDM conferences, selected those
researchers faced any particular challenges in those cases. In this       that mentioned any usage of graph tools, and extracted from them
paper, we compile studies that relied on graph tools and provide          information about which graph tools the authors employed, what
answers to the posed questions.                                           features of these tools were used, to what end the research in
                                                                          question was conducted, and if there were any particular
Keywords                                                                  challenges while using these tools.
Systematic Mapping Study, Graphs, Software Tools, Educational             The present study may be classified as a secondary study since we
Data Mining.                                                              base our approach on collecting other research works and
                                                                          assembling relevant information from them. Secondary studies
1. INTRODUCTION                                                           might be more typical of medical and social sciences but there are
The field of educational data mining (EDM) has significantly              proposed methodologies concerning secondary studies in software
expanded over the past two decades. It has attracted numerous             engineering as well [13]. Two kinds of secondary studies might be
researchers with various backgrounds around the common goal of            particularly important in this context: systematic review studies
understanding educational data through intelligent analysis and           and systematic mapping studies [20]. In both cases, there is a clear
using the extracted knowledge to improve and facilitate learning,         methodology that is set to reduce bias when selecting other
as well as educational process. In 2010, Romero and Ventura               research works, which gives these secondary studies the quality of
published a comprehensive overview of the field with 306                  being systematic. Some of the differences pointed out by Petersen
references [26]. In this review, the authors identified 11 categories     et al. [20] are that systematic reviews tend to focus on the quality
of educational tasks, two of which dealt with graph structures (for       of reviewed studies with the aim of identifying best practices,
brevity these will be referred to as graphs): social network              while systematic maps focus more on classification and thematic
analysis (SNA) and developing concept maps. However, the                  analysis but with less detailed evaluation of collected studies.
authors noted that these two categories featured a lower number of        Moreover, the same authors consider that the two study types
papers (15 or less references collected). Somewhat different              form a continuum, which might complicate some attempts at
categories of work were presented in another review of EDM [2]            categorization.
but they did not include any explicit references to graphs.               We categorize the present study as a systematic mapping study.
However, since that time, the interest in approaches and                  This classification is justified by the fact that:
technologies utilizing graphs has increased within EDM. In                      1.   we employed a concrete methodology,
addition to the results of a literature search on the topic, this could
                                                                                2.   we did not evaluate the quality of collected papers or
*Corresponding Author                                                                the presented results, but
                                                                                3.   we focused on identifying the employed graph tools and
                                                                                     the manner in which these tools were used, with the aim


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          of providing an overview of the current practice of                 3.   Proceedings of the 3rd International Conference on
          using graph tools within the EDM community                               Educational    Data   Mining     2010   (Pittsburgh,
                                                                                   Pennsylvania, USA)
However, we did not restrict our investigation to analysing
exclusively titles, abstracts, or keywords, but went through the              4.   Proceedings of the 4th International Conference on
complete texts to find the necessary information. This aspect                      Educational   Data   Mining     2011   (Eindhoven,
might better suit systematic reviews, but it does not change the                   Netherlands)
principal goal or character of our study.
                                                                              5.   Proceedings of the 5th International Conference on
The exact details of the employed methodology, including the                       Educational Data Mining 2012 (Chania, Greece)
research questions, sources of studies, and study selection criteria,
                                                                              6.   Proceedings of the 6th International Conference on
are given in Section 2. Section 3 contains the answers to the
                                                                                   Educational Data Mining 2013 (Memphis, Tennessee,
research question, most importantly the list of identified graph
                                                                                   USA)
tools and the trends in their usage in EDM. Section 4 covers the
potential limitations of the present study.                                   7.   Proceedings of the 7th International Conference on
                                                                                   Educational Data Mining 2014 (London, UK)
2. METHODOLOGY                                                                8.   Extended Proceedings of the 7th International
We mainly followed the guidelines given in [20] but also relied                    Conference on Educational Data Mining 2014 (London,
on the example of a mapping study presented in [21]. Given the                     UK), which included only the workshop papers
specificity of our study and the posed research questions, there
were some necessary deviations from the standard suggested              All the proceedings are freely offered as PDF files by the
procedure. The overall process of selecting papers and extracting       International Society of Educational Data Mining2 and may be
information, together with the resolution methods for non-              accessed through a dedicated web page.3
standard cases, is presented and discussed in the following             The papers from these proceeding represented our Level 0 (L0)
subsections.                                                            papers, i.e., the starting set of 494 papers. This set included
                                                                        different categories of papers: full (regular) papers, short papers,
2.1 Overview                                                            different subcategories of posters, as well as works from the
The first step was defining research questions to be answered by
                                                                        young researcher track (YRT) or demos/interactive events. The
the present study. The choice of research questions influenced the
                                                                        starting set did not include abstracts of invited talks (keynotes),
subsequent steps: conducting the search for papers, screening the
                                                                        prefaces of proceedings, or workshop summaries.
papers, devising the classification scheme, extracting data, and
creating a map.                                                         These papers were then searched and evaluated against our
                                                                        keyword criterion (KC), which led to a set of Level 1 (L1) papers.
2.2 Research Questions                                                  Our keyword string is of the form KC1 AND KC2 where KC1
We defined four principal research questions (RQ1-RQ4)                  and KC2 are defined in the following manner:
concerning the use of graphs and graph tools in studies by EDM
researchers:                                                                  •    KC1: graph OR subgraph OR clique

     •    RQ1: Which graph tools were directly employed by                    •    KC2: tool OR application OR software OR framework
          researchers in their studies?                                            OR suite OR package OR toolkit OR environment OR
                                                                                   editor
     •    RQ2: Which features of the employed graph tools were
          used by researchers?                                          The first part of the criterion (KC1) was defined to restrict the
                                                                        choice to papers that dealt with graphs, while the second part
     •    RQ3: What was the overall purpose of the research that        (KC2) served to narrow down the initial set of papers to those
          involved or relied on graph tools?                            mentioning some kind of a tool or program in general.
     •    RQ4: What features did researchers consider to be             When evaluating KC on each L0 paper, we did a case-insensitive
          missing or inadequate in the employed graph tools?            search for whole words only, whether in their singular form (as
                                                                        written in KC1 and KC2) or their plural form (except for the case
2.3 Search for Papers                                                   of “software”). This search also included hyphenated forms that
We searched through all the papers that were published in the           featured one of the keywords from KC, e.g., “sub-graph” was
proceedings of the EDM conference series till this date, i.e.,          considered to match the “graph” keyword.
papers from the first EDM conference in 2008 to the latest,
seventh, EDM conference in 2014. The latest EDM conference              As each proceedings file is a PDF document, we implemented a
was special because it also included four workshops (G-EDM              search in the Java programming language using the Apache
being one of them) for the first time. The papers from these            PDFBox4 library for PDF manipulation in Java. However, when
workshops were also considered in our search. This amounted to          extracting content from some papers, i.e., page ranges of a
eight relevant conference proceedings that represented the              proceedings file, we could not retrieve text in English that could
complete source of research works for our study:                        be easily searched. This was most probably caused by the fact that

     1.   Proceedings of the 1st International Conference on            2
                                                                            http ://www.educationaldatamining.org/
          Educational Data Mining 2008 (Montreal, Canada)
                                                                        3
                                                                            http://www.educationaldatamining.org/proceedings
     2.   Proceedings of the 2nd International Conference on            4
          Educational Data Mining 2009 (Cordoba, Spain)                     https://pdfbox.apache.org/
authors used different tools to produce camera ready versions in          2.5 Classification Scheme
PDF, which were later integrated into a single PDF file.                  The mode of tool usage was categorized in the following manner:
In these instances, usually one of the two main problems                         1.   CREATION (C) – the tool was developed by the paper
occurred: no valid text could be extracted or valid text was                          authors and introduced in the paper;
extracted but without spacing. In the case of invalid text, we had
to perform optical character recognition (OCR) on the                            2.   MODIFICATION (M) – the tool being modified, either
problematic page ranges. We used the OCR feature of PDF-                              through source code or by adding extensions/plugins;
XChange Viewer,5 which was sufficient as confirmed by our                             and.
manual inspection of the problematic page ranges (six problematic
                                                                                 3.   UTILIZATION (U) – the tool being utilized without
papers in total). In the case of missing spacing, we had to fine-
                                                                                      modification.
tune the extraction process using the capabilities of the PDFBox
library.                                                                  We also checked the distribution of the collected studies by the
                                                                          continent and the country corresponding to the authors’
This PDF library proved adequate for our task because we had to
                                                                          affiliation. In cases when there were authors from different
search only through PDF files and could customize the text
                                                                          countries, we indicated the country of the majority of authors, or,
extraction process to solve the spacing problem. However, in the
                                                                          if there was no majority then the country corresponding to the
case of a more varied data source, a more advanced toolkit for
                                                                          affiliation of the first author.
content indexing and analysis would be needed.

2.4 Screening of Papers                                                   2.6 Data Extraction and Map Creation
                                                                          Relevant data from L3 papers was extracted into a table that for
EDM researchers used many of our keywords with several
                                                                          each paper included the following information: author list, title,
different meanings, e.g., a graph could denote a structure
                                                                          proceedings where it was published, page range within the
consisting of nodes and edges, which was the meaning that we
                                                                          proceedings, answers to the research question and classifications
looked for, or some form of a plot. In order to determine the final
                                                                          according to the scheme presented in the previous subsection.
set of papers we performed a two-phase selection on L1 papers:
      1.   We examined the portions of L1 papers that contained           3. RESULTS AND DISCUSSION
           some KC1 keyword and eliminated papers that did not            An overview of the paper selection process is given in Table 1. In
           significantly deal with graphs (as structures) – this led      each step, the number of relevant papers is significantly reduced.
           to a set of Level 2 (L2) papers.                               As expected, the required effort in paper analysis was inversely
      2.   We read each L2 paper and eliminated those that did not        proportional to the number of selected papers. In the L1 step, the
           mention some use of graphs tools – this led to the final       usage of the keyword criterion relatively quickly eliminated many
           set of Level 3 (L3) papers.                                    papers. However, in subsequent steps, the selected papers had to
                                                                          be read, either partially (in the L2 step) or fully (in the L3 step).
In the first phase of selection, we examined the sentences that           The set of L3 papers represents a selection of EDM studies that
contain KC1 keywords. If this proved insufficient to determine the        were used to identify the usage patterns concerning graph tools.
nature or scope of use of the mentioned graphs, we read the whole         The list of the selected papers is publicly available.6
paragraph, and sometimes even the paragraph before and the
paragraph after. In these cases, we also checked the referenced                   Table 1. The number of selected papers at each step
figures, tables, or titles of the cited papers. If there were still any
                                                                          Step                                        Number of papers
doubts, we consulted the paper’s title and abstract, as well as
glanced over the figures looking for graph examples. If the               L0 – papers from EDM proceedings                   494
authors did not use graphs in their presented study or just made a
                                                                          L1 – papers containing keywords                    146
short comment about graphs giving an analogy or mentioning
graphs in the context of related or future work, we did not select        L2 – papers mentioning graphs                       82
the paper for the next phase.
                                                                          L3 – papers mentioning graph tools                  27
In the second phase of selection, we kept only those papers that
mention explicit use of a graph tool by the authors. In the cases
                                                                          Most studies (15) are from North America: USA (14) and Canada
when the actual use of a mentioned graph tool was not clear, the
                                                                          (1). Europe is represented by 8 studies from 6 countries: Czech
paper was selected if some of its figures contain a screenshot
                                                                          Republic (2), Spain (2), Germany (1), Ireland (1), Russia (1), and
featuring the tool or a graph visualized using that tool.
                                                                          UK (1). The remaining two continents represented are Asia
The term tool was considered rather broadly in the present study.         (Japan only) and Australia, each providing 2 studies. This
We did not restrict the search only to well-rounded software              somewhat resembles the EDM community present at the EDM
applications, but also included libraries for various computer            conferences and differs little from the structure of the EDM
languages, and even computer languages or file formats that were          community as reported in 2009 [2].
used by researchers to manipulate graphs. By making this
decision, we aimed to provide a greater breadth of information to         3.1 Overview of Graph Tools
researchers interested in applying graphs within their studies.           In Table 2, we list 28 graph tools mentioned in the 27 selected
                                                                          papers.

5                                                                         6
    http://www.tracker-software.com/product/pdf-xchange-viewer                http://www.acs.uns.ac.rs/en/user/31
                                  Table 2. Overview of graph tools from the selected papers
No       Tool      Usage                     Features                                       Purpose                         Issues
                                      mining
       
                      [14]
                    C ,        augmented graph grammar engine with            analyse student-produced argument           inefficiency
3    AGG Engine
                    U[15]             recursive graph matching                             diagrams                      in some cases
                               collect bullying data via web-form and
4      CASSI        C[19]                                                       support classroom management                   /
                                  use them to form a social graph
      CLOVER
5                   U[25]                 generate graph vis.                        (used in vis. in No. 2)                   /
     framework
                                provide a list of concepts and linking
6      Cmate        U[16]                                                          tabletop concept mapping                    /
                                   words to build a concept map
7       D3.js       U[17]           program interactive graph vis.           facilitate graph interpretation in EDA            /
                      [28]
8       DOT         U                      describe graphs                         (used in export in No. 14)                  /
                    C[9],                                                    understand student problem solving in
9     EDM Vis                       interactively vis. ITS log data                                                          WIP
                    M[10]                                                                    ITSs
10   eJUNG lib.     U[11]                   layout graphs                            (used in vis. in No. 14)                  /
     FuzzyMiner       [16]        generate fuzzy models (of student         discover and analyse student strategies in
11                  U                                                                                                          /
       (ProM)                         collaboration processes)                        tabletop collaboration
                                                                             identify similarities between LE course
12     Gephi         U[7]                     vis. graphs                                     content                          /
                                                                                   (used together with No. 22)
                                           describe graphs                    analyse student solutions of resolution
13    graphML       U[30]                                                                                                      /
                                    (of student resolution proofs)                             proofs
                      [11]
                    C ,
14      InVis                   interactively vis. and edit ITS log data     understand student interaction in ITSs          WIP
                   M[12, 28]
                                   interactively vis. learning object         understand how students perform and
15     LeMo         C[18]                                                                                                      /
                                               networks                     succeed with resources in LMSs and LPs
     Meerkat-ED                vis., monitor, and evaluate participation    analyse student interaction and messages
16                  C[22]                                                                                                      /
      toolbox                      of students in discussion forums                   in discussion forums
17      meud        U[24]         create diagrams (concept lattices)          analyse choices of study programmes              /
                        [6]                                                   study SNA metrics to improve student
18      Ora          U                  calculate SNA metrics                                                                  /
                                                                                      performance classifiers
                                                                             use student social data to predict drop-
                                 vis. networks and calculate network
19      pajek      U[3],[32]                                                   out and failure; understand growth of           /
                                               measures
                                                                                       communities on SNSs
                                                                                 explore ELE interaction data and
20       R           U[8]       use scripts to vis. ELE interaction data                                                     WIP
                                                                                           improve ELEs
                                                                                compare student problem solving-
     R – igraph
21                 U[5],[32]   create, refine, vis., and analyse networks    approaches in ITSs; understand growth             /
      package
                                                                                     of communities on SNSs
                                                                             identify similarities between LE course
22   RapidMiner      M[7]      create an operator for graph generation                         content                         /
                                                                                    (used together with No. 12)
23      RSP          C[4]         discover issues in the ITS process        support teachers through AT adaptation             /
     SEMILAR                                                                assess student natural language input in
24                  C[27]        semantic similarity methods for text                                                          /
       toolkit                                                                               ITSs
                                 generate graphs for student symbolic
25   SketchMiner    C[29]                                                   assess student symbolic drawings in ITSs           /
                               drawings; compare and cluster drawings
                                interactively vis. student interaction in    understand student problem solving in
26      STG          C[4]                                                                                                      /
                                                  ITSs                                       ITSs
                               perform analysis on content corpus and         support development of instructional
27    TRADEM        C[23]                                                                                                      /
                                    generate a concept map in ITSs                      content in ITSs
28     Visone       U[31]        vis. and analyse SNs, clique analysis        analyse user relationships in WBATs              /
The rows (graph tools) are ordered alphabetically by the tool            researchers considering the use of graphs to solve educational
name (the “Tool” column), which represents the answer to RQ1.            problems. For future work, we plan to include other publication
In general, we discovered a diverse list of infrequently used graph      series, even those that are not solely devoted to the EDM research.
tools. The usage of the graph tools, which represents the answer to      The results of such an attempt could demonstrate whether EDM
RQ2, is covered by the columns “Usage” and “Features”. In                practitioners from other regions of the world are more represented
“Usage”, we listed the mode of usage (see Section 2.5) and the           in the graph-based research than indicated by the results of the
references to the papers mentioning the graph tool. In “Features”,       present study.
we listed tool functionalities and capabilities that were created or
employed by the researchers. The most often used feature was to
visualize (vis.) graphs. The purpose of the selected studies, which
                                                                         6. ACKNOWLEDGMENTS
                                                                         The research presented in this paper was supported by the
represents the answer to RQ3, is given in the “Purpose” column.
                                                                         Ministry of Education, Science, and Technological Development
Researchers often analysed data from various interrelated systems:
                                                                         of the Republic of Serbia under Grant III-44010: “Intelligent
intelligent tutoring systems (ITSs) and adaptive tutorials (ATs),
                                                                         Systems for Software Product Development and Business Support
learning environments (LEs) including exploratory learning
                                                                         based on Models”.
environments (ELEs), learning management systems (LMSs),
learning portals (LPs), social network services (SNSs), web-based
authoring tools (WBATs), and web-based educational systems               7. REFERENCES
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