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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Learning Analytics to Assess Students' Behavior With Scratch Through Clickstream</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Daniel Amo</string-name>
          <email>damo@salleurl.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marc Alier</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Francisco J. García-Peñalvo</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>David Fonseca</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>María J. Casañ</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>La Salle, Universitat Ramon Llull</institution>
          ,
          <country country="ES">SPAIN</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Universitat Politècnica de Catalunya</institution>
          ,
          <country country="ES">SPAIN</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>University of Salamanca</institution>
          ,
          <country country="ES">SPAIN</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <abstract>
        <p>The construction of knowledge through computational practice requires to teachers a substantial amount of time and effort to evaluate programming skills, to understand and to glimpse the evolution of the students and finally to state a quantitative judgment in learning assessment. This suposes a huge problem of time and no adecuate intime feedback to students while practicing programming activities. The field of learning analytics has been a common practice in research since last years due their great possibilities in terms of learning improvement. Such possibilities can be a strong positive contribution in the field of computational practice such as programming. In this work we attempt to use learning analytics to ensure intime and quality feedback through the analysis of students behavior in programming practice. Hence, in order to help teachers in their assessments we propose a solution to categorize and understand students' behavior in programming activities using business technics such as web clickstream. Clickstream is a technique that consists in the collection and analysis of data generated by users. We applied it in learning programming environments to study students behavior to enhance students learning and programming skills. The results of the work supports this business technique as useful and adequate in programming practice. The main finding showns a first taxonomy of programming behaviors that can easily be used in a classroom. This will help teachers to understand how students behave in their practice and consequently enhance assessment and students' following-up to avoid examination failures.</p>
      </abstract>
      <kwd-group>
        <kwd>learning analytics</kwd>
        <kwd>clickstream</kwd>
        <kwd>scratch</kwd>
        <kwd>programming</kwd>
        <kwd>big data</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>The discipline of learning analytics allows to analyse student behavior patterns when
they interact with tools and online learning environments, set them in context with their
learning outcomes and draw conclusions to enhance the evaluation or improve the</p>
      <p>
        Copyright © 2018 for this paper by its authors. Copying permitted for private and academic purposes
learning process. Computational thinking [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] environments, such as programming ones,
can be adapted to integrated a Learning Analytics system. Therefore, any of the related
steps of a programming task can be analysed, namely: first actions of the student after
the presentation of the activity, analysis and design of the solution, process of
development and delivered code.
      </p>
      <p>The results obtained by this type of analysis can be considered as very valuable
information for any teacher, since it will allow them to know how each student is
evolving, what their current status is in relation to the proposed tasks and what their possible
risk to suspend according to trends extracted from previous analyses. Hence, the
student's follow-up in a programming environment could help teachers to provide better
support, enhance tutoring and adapt content or activities.</p>
      <p>
        In a programming activity each student has a different style and therefore can
develop a unique and different solution in comparison to the rest of their classmates. This
means that the teacher must spend a great deal of time analysing each of the possible
solutions delivered. In order to know what the student has done or what their behavior
has been during the development of the proposed activities, we can benefit from
automatic data collection and analytical techniques. The application of Learning Analytics
in programming practice now makes much more sense [
        <xref ref-type="bibr" rid="ref2 ref3">2-3</xref>
        ]. Therefore, in this work
we propose the use of the clickstream technique for the collection and analysis of
students’ interaction data.
      </p>
      <p>Clickstream is a technique used in web applications, typically in e-commerce, to
know how visitors behave in a website. Through the collection of clicks in the different
parts of the web pages and an analytical and visualization tool you can get an idea of
the behavior of the visitors. This information can be very valuable in refining the user
experience and adapting business strategies to maximize the conversion of visits into
sales.</p>
      <p>We propose that teachers use this technique of data analysis in visual programming
environments like Scratch. This will allow to know how students proceed in these
learning and programming environments and thus improve their tutoring and support to
students. The evaluation can also be improved due teachers will obtain objective
information about students’ deliveries.</p>
      <p>We also propose a modification of the Scratch tool to incorporate this click collection
technique. Students can develop applications in Scratch through the stacking of blocks
of instructions and in a very visual. This also facilitate the learning of programming
concepts. The modifications carried out allow capturing all the clicks made in this
visual programming environment.</p>
      <p>The clicks allow to reconstruct in some way everything that the student has done
during the development of the solution. This allows to know interesting aspects such as
if he has worked in class, which blocks have used, if he has applied the learned concepts
or if he has used the structures worked in the classroom. With this information we can
identify and classify the different ways of approaching the assigned programming task.
The collection of clicks can discover deeper aspects of students’ behavior such as
different programming styles according to the clicks done in zones of high concentration
of clicks.</p>
      <p>In the following sections the work is explained in terms of the state of the art,
methodology and results. The state of the art exposes how learning analytics and the study
of clicks can offer a new approximation to comprehend students behavior in learning
programming environments such as Scratch. The methodology section gives us the
opportuinity to explain how we modified the Scratch environment and which
methodologies were involved to collect students data through clicks interaction, which behavior
patterns were discobered from frst big data analysis and how those patterns were
positively correlated with assessments results. A conclusions section closes the paper
followed by an ethics statement about students collected data.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Theory</title>
      <p>
        Since 2010, the analysis of learning has become relevant in the field of research to
improve learning and the educational context in general. There is a concern in the
scientific community to understand how students learn to program from their beginnings
to advanced levels [
        <xref ref-type="bibr" rid="ref4 ref5 ref6 ref7">4-7</xref>
        ]. There is no single definition although the one proposed by
Erik Duval [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] that seems to be the most accurate to explain this situation when he
defines "Learning Analytics is about collecting traces that learners leave behind and
using those traces to improve learning".
      </p>
      <p>
        Different proposals encourage the use of learning analytics to improve the teaching
of programming. Sherman and Martin [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] propose an analytical approach to extract
patterns of behavior in student developers of App Inventor projects, while other authors
try to glimpse the progression of computational skills in such programming platform
[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. In comparison with our work, which also aims to identify patterns of behavior,
our approach is based on clicks instead of snapshots of the source code. This is an
approach not used so far in this type of programming environment that we hope can
provide interesting data to the scientific-educational community.
      </p>
      <p>
        Other authors [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] have proposed to understand how novice programmers approach
their first lines of code in conventional programming environments. His approach to
data collection is mixed, based on the keystrokes and events in the IDE, including
clicks. However, these authors have focused on the keystrokes and have not gone
deeply into the analysis of clicks.
      </p>
      <p>
        In business it is very common to analyse processes, resources and tasks. In
e-commerce, it is even an indispensable requirement. As a result, different techniques have
been developed to analyse the behavior of customers. In this paper we propose the use
of the clickstream technique used in business. The use of this technique is usually
applied in the e-commerce web pages [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. In this way the behavior of the clients can
explain their way of acting and create a taxonomy of behaviors to offer them more
related products or to guide them better through the website. In education this technique
can be applied to better understand students and to personalize learning. We understand
that clicks will offer additional information and complement current research.
      </p>
      <p>
        Blikstein et al. [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] has also used educational data mining techniques and learning
analytics in student code snapshots during their programming tasks. Blikstein intends
to use these approaches to automate assessments that would otherwise be impossible
for teachers to detect or to be very expensive in time. Our objective and methods of
analysis resemble those of this author, but the data capture differs and also the
modelling of capture, prediction, analysis and visualization [
        <xref ref-type="bibr" rid="ref14 ref15 ref16">14-16</xref>
        ].
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Methodology</title>
      <p>In order to capture the clicks, store them, analyse them and draw conclusions, we have
developed a solution supported by an architectural model based on events, a webservice
to send and store the interactions and a predictive model to forecast understandable
results for teachers.
3.1</p>
      <sec id="sec-3-1">
        <title>Click collection</title>
        <p>We have started the development from the original Scratch source code to create the
new programming context and click capturing system.</p>
        <p>The solution has been tested in different Scratch workshops held at La Salle Campus
Barcelona during 2017/2018. Due to the limited time available from the start of the
project until the first workshop, we have been able to develop a stable version, although
there is still a long way to go to complete all its possibilities. However, enough
interactions have been extracted to offer a first analysis and results of the tool.</p>
        <p>
          Figure 1 shows the flow of technologies used for the development of the modified
Scratch tool with Learning Analytics.
Fields et al. [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ] show in their research how it is possible to use learning analytics to
understand how students program in Scratch. The study is based on the analysis of the
time dedicated and the developed code of the solutions to the proposed problems. Their
results show different metrics in relation to application initialization and concurrent
execution. We think that a new approach based on clickstream is possible to discover
new behaviors.
        </p>
        <p>We consider at the same time that the analysis must be accompanied by an
assessment by the teaching staff to establish a relationship between qualifications and
behaviors. This relationship will allow teachers to obtain information on possible risks and
act accordingly. The use of rubrics will be enough to obtain a grade and analyse possible
relationship with the proposed behaviors.
3.3</p>
      </sec>
      <sec id="sec-3-2">
        <title>Behavior patterns</title>
        <p>To comprehend where the students interacted in Scratch we created an image with the
Scratch interface and the map of clicks.</p>
        <p>Blocked development (blocked). This type of behavior defines those
students who are having trouble with coding. The causes can be different, for
example by distractions, by attention to non-coding aspects such as design
and graphics or by a true ignorance of how to code the solution.
• Development at a normal (normal) pace. This type of behavior defines
those students who have a balance of development between the graphic
interface of the program and the coding.
• Rapid development based on trial-error (rapid). This type of behavior
defines those students who make rapid changes in the program and
constantly check the results.</p>
        <p>The discovery of these patterns is based on the number of clicks made on the “green
flag” button. Scratch allows you to execute the developed code by pressing a button
identified with a green flag. This action allows to indicate in which part or parts of the
code it have to start the execution, the initialization of the variables or the initialization
of the program status and to provide a structured execution flow. These aspects are
those that are assessed with the rubric and those that are intended to associate to the
behavior patterns during development of programming activities.</p>
        <p>We used a statistical approximation to analytically detect the three types of behavior
presented –blocking, normal, rapid-. This allows us to measure the pace of development
of the projects in relation to the class group. The interactions between the different
groups flow spontaneously, which changes their way of developing and final results
since they exchange knowledge throughout the development. Therefore, in the
statistical analysis all the clicks of all the groups of each workshop are considered.
Consequently, to extract the types of behavior we elaborated a statistical calculation in
relation to the median of the clicks made on the green flag button.</p>
        <p>The predictive model of behaviors is summarized in the following three points:
• Groups that click on the green flag below the 10% of the average are
considered blocked developments.
• Groups that click on the green flag above the 90% of the average are
considered rapid developments based on trial and error.</p>
        <p>• The other groups are considered as development at a normal pace.
In the analysis of collected data we found a relationship between the results of the
rubrics and the patterns detected. A close relationship between results and patterns will
help teachers personalize student learning. For example, a low qualification in the
rubric should be reflected in a blocking behavior. In some way this approach serves as an
automation of the rubric through student behavior. This information can be obtained in
real time. Consequently, the teacher may act before the student turns in the activity.
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Results</title>
      <p>Modifications in the Scratch source code have allowed to capture more than 38,000
clicks made by students among more than 30 different programming projects. The data
collected includes the position of the click on the screen, the date and time of the
moment of interaction, the object in which the click was made, the container of the object
and the action take, such as moving, adding or deleting blocks.</p>
      <p>The projects developed in the workshops have been evaluated by the two instruments
proposed in this work. On the one hand the code of the solutions has been evaluated
with a rubric. On the other hand, clicks have been introduced in the predictive model
to extract behaviors. This has allowed to obtain a score and a taxonomy for each of the
projects and find a first correlation between them.</p>
      <p>Table 1 shows the results of some of the projects assessed in terms of the rubric and
behaviour.
Results of the analysis of the bivariate correlation of the rubric grades and the clicks on
the green flag button are shown in table 3.
As observed in table 2, the correlation coefficient is close to 1. This indicates a strong
correlation between the evaluation by rubric and the clicks to the green flag button. The
p-value of the statistical test is less than 0.05. This indicate that there is a statistical
significance. Consequently, it can be affirmed that there is a correlation between those
projects in which students make rapid iterations of trial and error and good results. On
the other hand, the students who make fewer executions of the program are those who
have the simplest or unfinished programs.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Conclusions</title>
      <p>This work has been possible thanks to the release of the Scratch source code. It has
been possible to create a fork and add new software architectures that allow capturing
clicks of student interactions. A first predictive analysis correlated with real
assessments of the teachers shows how it is possible to analyse students behaviors in relation
to the clicks made in a visual programming environment based on blocks.</p>
      <p>The taxonomy of resulting behaviors are very valuable for teachers, who will be able
to personalize learning and improve the teaching environment. Now teachers can act
before students deliver incorrect or at least incomplete tasks.</p>
      <p>We hope to add new behavior patterns with a deeper analysis of the clicks beyond
the “green flag” button. Other behaviors can be differentiated through the analysis of
adding, modifying or eliminating blocks in the sprites’ code. This will be possible as
soon as we have more data.</p>
      <p>
        Our work is original in comparisson to data collection approximations of other
authors studies. Berland et al. [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], Martin&amp;Sherin[
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], Sherman&amp;Martin [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] and
Vihavainen et al [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] use snapshots of students’ code in different time intervals to study
and extract results in their analysis. No work have fully attention to the clickstream
technique. Furthermore, we tested and validated its feasibility to extract adequate
behavior patterns to enhance teacher feedback. Further work will consist in compare and
complement our work with the reuslts of these authors in terms of discovered pattern
behaviors.
      </p>
      <p>The investigation continues its course. The next phase consists in tracking students
along different courses. This will allow us to identify new behaviors and provide new
findings to enhance tutoring, following-up and evaluation of students.</p>
      <p>There are limitations linked to the original Flash. We hope to be able to make an
exhaustive follow-up course after course with the same students to improve the
accuracy of the prediction model. This will be possible when the new version of Scratch
based on HTML5 is published.
6</p>
    </sec>
    <sec id="sec-6">
      <title>Ethics References</title>
      <p>The collected data does not store sensitive or personal information of students. Any
possible sensitive data has been depersonalized since the same click capture. In this
way, any student interaction reaches the analysis phase absolutely anonymized.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          1.
          <string-name>
            <surname>García-Peñalvo</surname>
            ,
            <given-names>F.J.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Mendes</surname>
            ,
            <given-names>A.J.:</given-names>
          </string-name>
          <article-title>Exploring the computational thinking effects in pre-university education</article-title>
          .
          <source>Comput. Human Behav</source>
          .
          <volume>80</volume>
          ,
          <fpage>407</fpage>
          -
          <lpage>411</lpage>
          (
          <year>2018</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          2.
          <string-name>
            <surname>Lye</surname>
            ,
            <given-names>S.Y.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Koh</surname>
            ,
            <given-names>J.H.L.</given-names>
          </string-name>
          :
          <article-title>Review on teaching and learning of computational thinking through programming: What is next for</article-title>
          K-
          <volume>12</volume>
          ?, (
          <year>2014</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          3.
          <string-name>
            <surname>Berland</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          et al.:
          <article-title>Using Learning Analytics to Understand the Learning Pathways of Novice Programmers</article-title>
          .
          <source>J. Learn. Sci. 22</source>
          ,
          <issue>4</issue>
          ,
          <fpage>564</fpage>
          -
          <lpage>599</lpage>
          (
          <year>2013</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          4.
          <string-name>
            <surname>Grover</surname>
            ,
            <given-names>S.:</given-names>
          </string-name>
          <article-title>1e Unlocking the Potential of Learning Analytics in Computing Education</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          5.
          <string-name>
            <surname>Grover</surname>
            ,
            <given-names>S.</given-names>
          </string-name>
          et al.:
          <article-title>A Framework for Using Hypothesis-Driven Approaches to Support DataDriven Learning Analytics in Measuring Computational Thinking in Block-Based Programming Environments</article-title>
          .
          <source>ACM Trans. Comput. Educ</source>
          .
          <volume>17</volume>
          ,
          <issue>3</issue>
          ,
          <fpage>1</fpage>
          -
          <lpage>25</lpage>
          (
          <year>2017</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          6.
          <string-name>
            <surname>Ihantola</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          et al.:
          <article-title>Educational Data Mining and Learning Analytics in Programming</article-title>
          .
          <source>In: Proceedings of the 2015 ITiCSE on Working Group Reports - ITICSE-WGR 15</source>
          . pp.
          <fpage>41</fpage>
          -
          <lpage>63</lpage>
          ACM Press, New York, New York, USA (
          <year>2015</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          7.
          <string-name>
            <surname>Martin</surname>
            ,
            <given-names>T.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Sherin</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          :
          <article-title>Learning Analytics and Computational Techniques for Detecting and Evaluating Patterns in Learning: An Introduction to the Special Issue</article-title>
          .
          <source>J. Learn. Sci. 22</source>
          ,
          <issue>4</issue>
          ,
          <fpage>511</fpage>
          -
          <lpage>520</lpage>
          (
          <year>2013</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          8.
          <string-name>
            <given-names>Learning</given-names>
            <surname>Analytics</surname>
          </string-name>
          and
          <article-title>Educational Data Mining | Erik Duval's Weblog</article-title>
          , https://erikduval.wordpress.com/
          <year>2012</year>
          /01/30/learning-analytics-and
          <article-title>-educational-data-mining/.</article-title>
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          9.
          <string-name>
            <surname>Sherman</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Martin</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          :
          <article-title>Learning analytics for the assessment of interaction with App Inventor</article-title>
          .
          <source>In: 2015 IEEE Blocks and Beyond Workshop (Blocks and Beyond)</source>
          . pp.
          <fpage>13</fpage>
          -
          <lpage>14</lpage>
          IEEE (
          <year>2015</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          10.
          <string-name>
            <surname>Fields</surname>
            ,
            <given-names>D.A.</given-names>
          </string-name>
          et al.:
          <article-title>Combining Big Data and Thick Data Analyses for Understanding Youth Learning Trajectories in a Summer Coding Camp</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          11.
          <string-name>
            <surname>Vihavainen</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          et al.:
          <article-title>How novices tackle their first lines of code in an IDE</article-title>
          .
          <source>In: Proceedings of the 14th Koli Calling International Conference on Computing Education Research - Koli Calling '14</source>
          . pp.
          <fpage>109</fpage>
          -
          <lpage>116</lpage>
          ACM Press, New York, New York, USA (
          <year>2014</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          12.
          <string-name>
            <surname>Senecal</surname>
            ,
            <given-names>S.</given-names>
          </string-name>
          et al.:
          <article-title>Consumers' Decision-Making Process and Their Online Shopping Behavior: A Clickstream Analysis Consumers' Decision-Making Process and Their Online Shopping Behavior: A Clickstream Analysis Consumers' Decision-Making Process and Their Online Shopping Behavior: A Clickstream Analysis</article-title>
          .
          <article-title>(</article-title>
          <year>2003</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref13">
        <mixed-citation>
          13.
          <string-name>
            <surname>Blikstein</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          et al.:
          <article-title>Programming Pluralism: Using Learning Analytics to Detect Patterns in the Learning of Computer Programming</article-title>
          .
          <source>J. Learn. Sci. 23</source>
          ,
          <issue>4</issue>
          ,
          <fpage>561</fpage>
          -
          <lpage>599</lpage>
          (
          <year>2014</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref14">
        <mixed-citation>
          14.
          <string-name>
            <surname>Gómez-Aguilar</surname>
            ,
            <given-names>D. A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>García-Peñalvo</surname>
            ,
            <given-names>F. J.</given-names>
          </string-name>
          , &amp;
          <string-name>
            <surname>Therón</surname>
            ,
            <given-names>R.</given-names>
          </string-name>
          (
          <year>2014</year>
          ).
          <article-title>Analítica Visual en eLearning</article-title>
          .
          <source>El Profesional de la Información</source>
          ,
          <volume>23</volume>
          (
          <issue>3</issue>
          ),
          <fpage>236</fpage>
          -
          <lpage>245</lpage>
          . doi:
          <volume>10</volume>
          .3145/epi.
          <year>2014</year>
          .may.03
        </mixed-citation>
      </ref>
      <ref id="ref15">
        <mixed-citation>
          15.
          <string-name>
            <surname>Gómez-Aguilar</surname>
            ,
            <given-names>D. A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Hernández-García</surname>
          </string-name>
          , Á.,
          <string-name>
            <surname>García-Peñalvo</surname>
            ,
            <given-names>F. J.</given-names>
          </string-name>
          , &amp;
          <string-name>
            <surname>Therón</surname>
            ,
            <given-names>R.</given-names>
          </string-name>
          (
          <year>2015</year>
          ).
          <article-title>Tap into visual analysis of customization of grouping of activities in eLearning</article-title>
          .
          <source>Computers in Human Behavior</source>
          ,
          <volume>47</volume>
          ,
          <fpage>60</fpage>
          -
          <lpage>67</lpage>
          . doi:
          <volume>10</volume>
          .1016/j.chb.
          <year>2014</year>
          .
          <volume>11</volume>
          .001
        </mixed-citation>
      </ref>
      <ref id="ref16">
        <mixed-citation>
          16.
          <string-name>
            <surname>Amo</surname>
            ,
            <given-names>D.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Alier</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Casany</surname>
            ,
            <given-names>M.J.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Mayol</surname>
          </string-name>
          , E.:
          <article-title>A learning analytics tool with hybrid graphical and textual interpretation generation</article-title>
          .
          <source>Proceedings of the Fourth International Conference on Technological Ecosystems for Enhancing Multiculturality</source>
          , pp.
          <fpage>327</fpage>
          -
          <lpage>333</lpage>
          . ACM, Salamanca, Spain (
          <year>2016</year>
          )
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>