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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Validating Performance of Group Formation Based on Homogeneous Engagement Criteria in MOOCs</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Luisa Sanz-Martínez</string-name>
          <email>luisa@gsic.uva.es</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Alejandra Martínez-Monés</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Miguel L. Bote-Lorenzo</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Yannis Dimitriadis</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>GSIC/EMIC, Universidad de Valladolid</institution>
          ,
          <addr-line>Valladolid</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <abstract>
        <p>Active pedagogies can improve the pedagogical effectiveness of MOOCs. Group formation, an essential step in the design of small-group learning activities, can be challenging in MOOCs given the scale and the wide variety of students' behaviors in such contexts. In this paper, we further analyze the suitability of applying the students' engagement in the course as grouping criterion to form small groups in MOOC contexts. The impact of a grouping strategy based on requiring homogeneity among the students' engagement of the group is examined in a real MOOC context. In a preliminary stage the results have been analyzed in terms of peer interactions, active students per team and students' satisfaction. These results have been also compared with those in prior interventions in real MOOCs, thus validating previous findings about the suitability of this approach. The role of the timing of grouping was also examined by carrying out two collaborative activities at different weeks (the fourth and the sixth). A consistent improvement of all indicators was observed in the second intervention and its possible causes are discussed.</p>
      </abstract>
      <kwd-group>
        <kwd>MOOC</kwd>
        <kwd>CSCL</kwd>
        <kwd>Automatic Group Formation</kwd>
        <kwd>Engagement</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Since their emergence in 2008, MOOCs (Massive Open Online Courses) have allowed
the free delivery of knowledge to millions of people around the world. Due to the need
of eventually hosting a huge number of enrollments, most MOOCs adopt pragmatic
instructional designs that scale easily and run smoothly with massiveness. The most
popular type of MOOC, called xMOOC, is based on an instructivist model that provides
educational content, in text or video format, and assesses the achievement of learning
by means of quizzes. In xMOOCs, the interactions among learners are mostly limited
to forums and peer reviews. This type of instructional design does not include
pedagogic methods which actively involve students in the learning process, such as
collaborative learning or project based learning [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. There is evidence that these active
pedagogies may enrich learning through the acquisition of specific competences while
promoting students’ engagement [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. To carry out these active pedagogies, the teacher
needs to orchestrate many tasks, an endeavour that poses many difficulties in massive
and variable scale context. One of these orchestration tasks is the management of teams
[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], i.e., small groups of students focused on carrying out a task together.
      </p>
      <p>Copyright © 2018 for this paper by its authors. Copying permitted for private and academic purposes</p>
      <p>
        The management of groups in MOOC contexts is quite challenging [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] mainly due
to the massiveness and the high variability of students’ profiles and behaviors in this
type of courses. Due to the interest for including CL in MOOCs, several authors have
tackled the group formation problem in these contexts [
        <xref ref-type="bibr" rid="ref5 ref6 ref7 ref8 ref9">5,6,7,8,9</xref>
        ] addressing the
challenge through different perspectives. These perspectives include a variety of
criteria (e.g., knowledge, personality, preferences, affinities, location, motivation),
grouping approaches (e.g., criteria-based homogeneity or heterogeneity, random
grouping) and technological aspects (e.g., social network metrics, natural language
processing, classification algorithms). Although some of the aforementioned research
studies have considered the behavior of the students during the course [
        <xref ref-type="bibr" rid="ref5 ref7 ref9">5,7,9</xref>
        ], none of
them has considered the students’ engagement dynamics in MOOCs, which is a feature
that characterize this type of courses [
        <xref ref-type="bibr" rid="ref10 ref11">10,11</xref>
        ], as a main factor to inform the group
formation process. Thus, to create small groups where collaboration can succeed in
open and massive context, it is worth to consider the use of students’ engagement in the
process [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Furthermore, the application of engagement as grouping criterion to form
homogeneous or heterogeneous teams should be checked, thus analyzing the outcomes
of each approach.
      </p>
      <p>In this paper, we present a study where the suitability of using the students’
engagement in the course as homogeneous grouping criterion is analyzed and
discussed. The rest of the paper is structured as follows. Firstly, we present our prior
work in order to introduce a conceptual and technological framework we have
developed as well as our previous interventions. Then, we describe the study presented
in this paper and discuss its preliminary results and findings.
2.</p>
    </sec>
    <sec id="sec-2">
      <title>Prior Work</title>
      <p>The present study is part of a wider research process aimed at supporting teachers in
the management of collaborative groups in MOOCs. In the first iteration, we performed
a literature review which, together with the gathering of experts’ opinions, produced a
preliminary version of a framework intended to organize the available information
about the issue of managing collaborative groups in MOOCs. In the second iteration of
the process, we generated two instrumental artifacts (a guide and a tool prototype) that
were tested in two exploratory studies. The components of the framework and the main
findings of these studies are described in the next subsections.
2.1</p>
      <sec id="sec-2-1">
        <title>MyGang Framework</title>
        <p>
          MyGang (Mooc analYtics for Group Assignment, moNitoring and reGrouping)
framework [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] is aimed at organizing the relevant information regarding the issue of
managing collaborative groups in MOOCs and to support those interested in deploying
group activities in these educational contexts. It was developed based on a literature
review and experts’ opinions, and it has been enriched and evaluated through iterative
interventions. The framework is currently composed of five elements:
        </p>
        <p>Context (MyGang_C) presents, in a structured fashion, the intrinsic features
(Massive, Open, Online and Course) of MOOC contexts, and their derived extrinsic
properties. This information is used in the Design Guide (MyGang_DG), to make
teachers reflect on the impact of the context on the management of groups.</p>
        <p>Grouping Factors (MyGang_GF), shown in Figure 1, depicts a hierarchical
classification of the factors that influence the management of collaborative groups in
MOOCs. The possible factors are divided into two main subsets related to pedagogy
and technology. The pedagogical factors are also split into three categories, i.e., (i)
Learning Design, which are aspects related to the learning design decisions that affect
the group composition; (ii) Dynamic Data, that include the information monitored and
updated while the course is running, (mostly the trace data that emerge through students'
learning activities and interactions); and (iii) Static Data, referred to the information
about the students that is not updated during the course enactment (e.g., demographics,
preferences, etc.). This information is collected usually through surveys at the
beginning of the course. These pedagogic factors are also used in the Design Guide
(MyGang_DG) to support the decision making on the design of the groups activity and
the configuration of the teams.</p>
        <p>Architecture (MyGang_A) of the envisioned supporting tool to manage groups in
MOOCs, is shown in Figure 2. It presents a high-level design of the envisioned
groupmanagement supporting tools’ structure. It uses the pedagogical Grouping Factors (i.e.,
Learning Design, Dynamic Data and Static Data) as data inputs for the system and
depicts them in green in the figure. The system is composed of several modules
including adapters to import/export data from/to the MOOC platform: (a) a Dynamics
Processing Module, to gauge and estimate dynamic factors (such as the engagement,
the emerging role or the dropout probability) using the raw dynamic data collected from
the platform; and (b) a Grouping Module, to configure the group structures based on
the collected data and on the specifications given by the teachers.</p>
        <p>Design Guide (MyGang_DG is a questionnaire that includes guidance and
recommendations. It consists of four sections. The first section is related to the MOOC
context features depicted in MyGang_C in order to make teachers aware of the context
aspects that affect group formation. It includes questions so that teachers can reflect
and select concrete characteristics of the envisioned MOOC using the researcher
recommendations. The following three sections correspond to the three dimensions of
the pedagogical factors of MyGang_GF and should be filled out once for each group
activity to be designed. Teachers have to configure the learning design characteristics
of the group activity and elicit the static and dynamic data factors that can be considered
to configure the groups by using them as grouping criteria. In its current state, the guide
may be used in a co-design process in the form of interviews with the teachers in order
to discuss every item included in it. The researcher should give advice about the
possible advantages and drawbacks of every decision made by teachers based on prior
experiences, literature and experts’ opinions.</p>
        <p>Tool (MyGang_T) is an implementation of MyGang_A that, at the moment, includes
an early version of an interface module, which receives the input (e.g., group size,
grouping criteria, etc.) through a configuration file and produces scheduled reports
about the groups’ performance. The adapters have been programmed to meet the
Canvas Network platform requirements and the grouping module to implement the
group configuration specifications provided by teachers in each intervention. The
functionalities of the rest of modules have been developed in order to satisfy the
concrete specifications of the three studies carried out until now.
2.2</p>
      </sec>
      <sec id="sec-2-2">
        <title>Interventions and Findings in Previous Two Studies</title>
        <p>
          In our first exploratory study [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ], we found out that a grouping policy based on the use
of students’ engagement criteria to form homogeneous teams achieved several
advantages compared to a random grouping, even though the latter policy had been
improved by the segregation of no-show students. In this study, we carried out two
experiments, one in the first half of the course and other in the second one. The main
advantages showed by the homogeneous-engagement grouping approach over the
random approach were:
● it obtained many groups where all members were active, while the random
approach did not achieve any group of these characteristics;
● it resulted in a number of teams with a single active member much lower than the
random approach (four times lower in the first experiment of the study and ten
times lower in the second one;
● it obtained a higher number of interactions per team and per user;
● it resulted in a greater degree of students’ satisfaction.
        </p>
        <p>In this intervention, the first version of MyGang_DG and MyGang_T were used in
order to design and implement the configuration of the groups, thus validating their
utility.</p>
        <p>
          The second study [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ], served us to enrich MyGang_DG testing it with teachers,
who are widely experienced in Collaborative Learning. Furthermore, MyGang_T was
also improved by adding new functionalities that allowed us to implement different
levels of priorities to set the criteria, as well as to use Dynamic Data (i.e., engagement
level) and Static Data (gathered from a survey) as grouping criteria. We checked the
application of Static Data (i.e., language and preferred days for working in the course)
to form homogeneous cohorts. Then, heterogeneity among the engagement level of the
team members was applied in each cohort as a second level of criteria. The results of
this grouping policy were worse than those obtained in the first study regarding the
variables analyzed:
● it resulted in many groups (most of the total number of active teams) with only one
or two active participants;
● it achieved to form very few teams with three active participants (less than 10% of
the total);
● it did not obtain any group with four or five (the number of members of the team)
that were active;
● the number of interactions per team and per user was lower than in the homogenous
approach of our prior study.
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Description of the Study</title>
      <p>In this section, we report on the design of a third study intended to accumulate evidence
to validate prior findings. In addition, we also explored the usefulness of two of the
aforementioned instruments, the design guide and the tool, developed within the
framework (MyGang_DG and MyGang_T) in order to provide support to teachers. The
study was carried out in the second edition of the MOOC used to deploy our first
exploratory study.
3.1</p>
      <sec id="sec-3-1">
        <title>Objective</title>
        <p>This study was carried out to get additional data and evidence about the performance
of the homogeneous-engagement grouping approach used in our first study with a
different students’ population. Therefore, the main objective of this study was to
validate the suitability of the homogeneous engagement grouping approach (i.e.,
application of homogeneous engagement criteria to form small groups) to produce
successful teams.</p>
        <p>The success of the resulting groups was measured in terms of: (a) participation level
in the collaborative activity (i.e., number of posted messages and number of active
participants in each team) and (b) satisfaction of students regarding the collaboration
carried out in their team. The final goal is to validate if this approach is able to achieve
teams with several active students which carry out many interactions within their group
and also to minimize the number of teams with a single active student. The perception
of the students about the collaboration within their teams, and its relationship with the
grouping strategy is also covered in the study.
3.2</p>
      </sec>
      <sec id="sec-3-2">
        <title>Methodology</title>
        <p>
          This study is part of a wider multidisciplinary project that involves education and
technology. The study is mainly guided by a DSRM (Design Science Research
Methodology) [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ] that is used in Information Systems research and it is oriented to
develop and evaluate different type of artifacts in order to solve research problems. This
methodology is iterative and evolutionary and, in our project, it is being applied
beginning with explorative iterations and moving towards more evaluative ones to
validate the artifacts generated in prior cycles. This way, we are conferring this
methodology a nuance that takes it closer to DBR (Design Based Research) [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ] used
in Social Sciences. We are currently on the third cycle of the process as shown in Figure
3.
3.3
        </p>
      </sec>
      <sec id="sec-3-3">
        <title>Context</title>
        <p>The study was carried out in a seven-week MOOC that taught translation of economy
and finance-related texts from Spanish to English. The course was offered by the
University of Valladolid, Spain and it was deployed in the Canvas Network platform
between March the 12th and April the 30th, 2018. The enrollment was closed at the end
of the first week to allow us to configure properly the groups for the collaborative
assignments. A free certificate was granted to the students who completed the
mandatory assignments (one per week) in addition to the two surveys.</p>
        <p>The total number of enrollments was 1028, and 653 of these students fulfilled the
mandatory survey that was a requirement to see the course content. To obtain the
certificate it was necessary to complete a compulsory assignment per week together
with a final satisfaction survey. 173 students achieved the certificate (almost 17% of
the enrolled students and 26.5% of those who accessed to the course content).
3.4</p>
      </sec>
      <sec id="sec-3-4">
        <title>Experimental Design</title>
        <p>To implement the homogeneous-engagement grouping approach, learning analytics
were employed to track MOOC learners' activities using the platform API (Application
Program Interface).</p>
        <p>
          Three types of elements were taken into account to gauge student engagement:
engagement with course content, engagement with course assessment, and engagement
with course discussion [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ]. Then, we used the following variables (codes indicated
within brackets) as measures of student engagement:
● Number of page views (coded as [num_page_view]), as a measure of the
engagement with content.
● Number of seconds of connection time in the course (coded as [sec_conn_time], as
a second measure of engagement with content.
● Number of submitted assignments (coded as [num_subm_assi]), as a measure of
engagement with assessments and commitment with the course.
● Number of posted messages in forums (coded as [num_post_mess]), as a measure
of the engagement with discussions and active participation in the course.
        </p>
        <p>
          The algorithm selected for implementing the homogeneous grouping was k-means
clustering as it has shown to be effective with large datasets [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ]. Since the k-means
algorithm does not necessarily result in clusters with the same size, the process was
slightly modified by applying a same-size k-means variation1to ensure that the resulting
clusters had the same size. Prior to the clustering process, the four engagement
indicators were standardized in order to ensure that they had the same weight in the
calculations of the grouping algorithm, as recommended in [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ].
        </p>
        <p>This strategy was applied to the group formation process in two collaborative
assignments planned for two different weeks of the course, i.e., at weeks four and six
respectively. It is noteworthy that in both assignments, a window of 21 days was used
to trace data about the students’ activity in the platform. For the first collaborative</p>
        <sec id="sec-3-4-1">
          <title>1 https://elki-project.github.io/tutorial/same-size_k_means</title>
          <p>activity, this length was the distance between the course start and the beginning of the
activity. The same window length was also applied when obtaining the trace data in the
second assignment.</p>
          <p>To measure the experimental results, we gathered data about the activity carried out
in each team (i.e., exchanged messages, active participants) using the Canvas Network
API. We also collected information from four surveys deployed in the course. The first
one was necessary to access the course content and the following surveys were intended
to capture the students’ satisfaction. Furthermore, the messages sent from the students
to the teachers through the platform during the collaborative assignments were also
captured in order to detect potential complaints and issues. Table 1 shows the data
sources used in the experiments and figure 4 depicts the timeline of this data gathering.
to measure the effects of the grouping strategy employed.</p>
        </sec>
      </sec>
      <sec id="sec-3-5">
        <title>Source</title>
      </sec>
      <sec id="sec-3-6">
        <title>Description</title>
        <sec id="sec-3-6-1">
          <title>Surveys [SurX]</title>
        </sec>
        <sec id="sec-3-6-2">
          <title>Platform use Analytics [AnaX]</title>
        </sec>
        <sec id="sec-3-6-3">
          <title>Communication from students to teachers [Com]</title>
          <p>Course surveys composed of open-ended and closed questions
including 4-point Likert items (1 = strongly disagree, 2 =
disagree, 3= agree, 4= strongly agree, + don’t know/no answer)
were administered:
-[Sur1]. – Mandatory survey at the beginning of the course to get
ethnographic data and preferences of the students.
-[Sur2]. - Optional mini-survey at the end of the 4th week activity
to score satisfaction and gather positive and negative perceptions
regarding the collaboration carried out in the teams.
-[Sur3]- Optional mini-survey at the end of the 6th week activity
to score satisfaction, and gather positive and negative perceptions
regarding the collaboration carried out in the teams.
-[Sur2]. - At the end of the course (mandatory) to obtain students’
satisfaction with the course.</p>
          <p>Canvas LMS API was used to collect indicators about:
-[Ana1], [Ana3]. - Students’ engagement variables (i.e.,
[sec_conn_time], [num_page_view], [num_subm_assi] and
[num_post_mess]) used to inform the group formation process.
-[Ana2], [Ana4]. - Activity carried out during the group
assignments (active teams, activity carried out within a team),
used to evaluate the impact of the strategy implemented.</p>
        </sec>
        <sec id="sec-3-6-4">
          <title>Emails and personal messages sent in the Canvas platform from</title>
          <p>the students to the teachers during the collaborative assignments
(4th and 6th weeks).
After a preliminary analysis of the data gathered from the Canvas API we observed that
percentages of interactions and active students per team seemed to be in a similar range
of values than in the first study.</p>
          <p>The satisfaction of the students with the collaboration carried out in their teams was
measured in a different manner than in the previous study. In the study reported in this
paper the students were required to score this satisfaction in a 0 to 10 scale just when
the assignment finished. In the fourth week, they scored it 6.64 and in the sixth the
average score was 7.78. In the prior edition of this MOOC the students had to express
their agreement or disagreement with the statement “the collaboration carried out in my
team was satisfactory” and they agreed in a 55% in the fourth week and in 70% in the
sixth.</p>
          <p>Therefore, although a deeper analysis of this data must be carried out, we can share
these preliminary findings:
1. The number of teams with one single active participant represents a low
percentage of the total number of active teams, and it is below 10% in the sixth
week.
2. The grouping approach results in groups with many active members (i.e., more
than the half of the total number of members of the team). In the experiment of
the sixth week this type of teams exceeds 75% of the active teams.
3. The number of interactions per team remained in the same range as in the previous
intervention and it was more than the double of that in the random approach, used
as control group in the first study.
4. The students’ satisfaction with the collaboration carried out in their team is
positive.
5. The second experiment (carried out in the sixth week) achieved better results than
the first one (carried out in the fourth week) in terms of peer interactions, number
of active members per team and students’ satisfaction. This fact confirmed a
finding of the prior study and we deem that it can be due to two reasons:
a. The engagement of the students is more stable in the second half of the course
and this approach based in engagement improves its accuracy
b. The students are familiar with the mechanics to carry out a collaborative task
(instructions, recommendations, available tools in the platform) and this
information allows them to perform better thus increasing their satisfaction.
5.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Conclusions</title>
      <p>This study served us to get additional evidence about the eventual advantages of
applying homogeneous-engagement policies to form small-groups in MOOC contexts.
After a preliminary analysis of data, several advantages of the
homogeneousengagement grouping approach have been confirmed.</p>
      <p>When the objective to create small groups in learning contexts is to carry out a
collaborative task, an unavoidable requirement is to achieve more than one active
student in the group. The approach validated in this paper has shown to achieve better
results in this regard than a random grouping.</p>
      <p>It was also shown that this approach achieves better results than a random grouping
in terms of peer interactions and number of active students per team and it obtained a
considerable percentage (40% in the fourth week and more than 75% in the sixth week)
of teams, in which with more than half the students of the team were active. This feature
does not guarantee an enriching collaboration but it is a first step towards achieving
such objective. Also, the satisfaction of students with the collaboration carried out in
teams formed with this approach is reported by them as positive.</p>
      <p>Finally, all these positive results were even better when the experiment is carried
out a second time and deployed using data analytics from the second half of the course.</p>
      <p>In the short term, we plan to keep on exploring the usefulness of MyGang_DG and
MyGang_T in other MOOC platform (MiriadaX) which offers different functionalities
for team activities. We also want to check the differences between a random grouping
and the application of heterogeneous criteria regarding different variables. In the future,
we would like to deepen in the outcomes of applying homogeneity on Dynamic Factors
by testing it with different indicators and variables like the students’ connection
patterns.
6.</p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>This research has been partially funded by the Spanish State Research Agency (AEI)
and the European Regional Development Fund, under project grants
TIN2014-53199C3-2-R and TIN2017-85179-C3-2-R, the Regional Government of Castilla y León and
the European Regional Development Fund, under project grant VA082U16, the
European Commission, under project grant 588438-EPP-1-2017-1-EL-EPPKA2-KA
and the Universidad de Valladolid (UVa).</p>
    </sec>
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