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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Multimodal Learning Analytics Research in the Wild: Challenges and their Potential Solutions</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Pankaj Chejara</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Reet Kasepalu</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Luis P. Prieto</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>María Jesús Rodríguez-Triana</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Adolfo Ruiz-Calleja</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Shashi Kant Shankar</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>School of Digital Technologies, Tallinn University</institution>
          ,
          <addr-line>Tallinn</addr-line>
          ,
          <country country="EE">Estonia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Education Science, Tallinn University</institution>
          ,
          <addr-line>Tallinn</addr-line>
          ,
          <country country="EE">Estonia</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Universidad de Valladolid</institution>
          ,
          <addr-line>Valladolid</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Multimodal Learning Analytics (MMLA) has enabled researchers to address learning in physical settings which have long been either overlooked or studied using observational methods. With the use of sensors, researchers have been able to understand learning through an entirely new perspective (e.g., analyzing heart-rate variability to find collaboration indicators). Consequently, MMLA has grown significantly in the past few years, moving from a nascent stage towards a more mature field. It raises a question on how the MMLA researcher can move further, i.e., the transition towards practice which started getting researchers' attention. This paper discusses the challenges we faced while conducting MMLA studies in classroom settings over four years and potential solutions to realize the goal of transitioning MMLA research to educational practice. This paper aims to start a discussion in the field of MMLA over the transition of research to practice.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Collaboration analytics</kwd>
        <kwd>Multimodal learning analytics</kwd>
        <kwd>Machine learning</kwd>
        <kwd>Collaboration intervention</kwd>
        <kwd>MMLA</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Traditional log-based Learning Analytics (LA) has utilized digital traces of students’ activities to
understand learning and its context, which only provides a partial picture of a learning situation
that occurs across spaces (e.g., collaborative learning in face-to-face settings). To address this
issue, researchers have started employing various types of data sources (e.g., audio, video) to
complement log-based LA analysis [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. This research field is known as Multimodal Learning
Analytics (MMLA) [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. MMLA enables researchers to harness the multimodal educational data
collected from digital as well as physical spaces. MMLA was proposed for the first time in the
workshop held at the ICMI conference in 2012 [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Since then the field has made significant
progress, resulting in moving from a nascent research field towards a more mature field [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        Researchers have employed MMLA for studying a range of learning scenarios (e.g.,
projectbased learning [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], collaborative learning [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]) with the use of a wide variety of data sensors
(e.g., audio, video, eye-gaze, physiological) [
        <xref ref-type="bibr" rid="ref1 ref7">1, 7</xref>
        ]. These data sensors have allowed researchers
to investigate the physical space of learning, thus enabling a more holistic understanding
of learning behavior for researchers as well as teachers. Consequently, the field has gained
substantial attention from researchers to understand how learners work together in
ComputerSupported Collaborative Learning (CSCL) activities which often happen across spaces (e.g.,
digital and physical spaces). [
        <xref ref-type="bibr" rid="ref5 ref7">5, 7, 8</xref>
        ].
      </p>
      <p>
        MMLA Researchers have explored the relationship between various data features and
collaboration constructs (e.g., collaboration quality) [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] and have developed machine learning models
to automate the estimation of collaboration constructs. The number of MMLA research studies
in authentic settings has grown significantly in the past few years [ 9]. However, this number is
still skewed toward laboratory settings when considering MMLA research in CSCL.
      </p>
      <p>The majority of current MMLA research in CSCL research has been conducted in laboratory
settings [10] which allow more controlled settings than classroom settings. However, students
may not necessarily behave in a similar way when participating in a learning activity in
laboratory and classroom settings [11]. Furthermore, in our previous vignette study where we
investigated teachers’ trust in the MMLA dashboard for CSCL, teachers indicated trusting the
data from the dashboard and proposing a variety of interventions in the imagined classroom [12].
However, we were unable to replicate those findings in authentic settings. These concerns raise
the need of conducting MMLA research in classroom settings. However, given its technological
complexity, the use/implementation of MMLA in classroom settings is not straightforward.</p>
      <p>In this paper, we share our experience of conducting MMLA research in authentic settings
and building MMLA tools for supporting teachers [13, 14]. We conducted two iterations of
the MMLA study in Estonian high school and vocational school. We collected multimodal
educational data to build automated models for collaboration behavior to build a guiding tool
to support teachers with intervention strategies during collaborative learning.</p>
    </sec>
    <sec id="sec-2">
      <title>2. MMLA research studies on collaborative learning</title>
      <p>The goal of our research was to build automated models which can estimate collaboration
quality and its underlying dimensions (e.g., argumentation) as per Rummel et al. [15] framework,
and integrate the developed models in intervention guiding tools to support teachers in the
classrooms. We developed our prototype in two iterations (later explained). Table 1 presents
the stakeholders involved in both iterations.
iteration teachers students researchers schools</p>
      <sec id="sec-2-1">
        <title>2.1. Iteration-1: Using a Raspberry Pi-based prototype</title>
        <p>
          In our first iteration (Figure 1), we developed a Raspberry Pi-based prototype to capture the
speaking behavior of participants of a group working on a given problem in classroom settings.
The prototype was used along with Etherpad1 which allowed the group’s participants to draft
solutions to the given problem. We collected multimodal data (audio and logs) from two
classroom sessions in an Estonian High school during a collaborative learning activity with the
same teacher [
          <xref ref-type="bibr" rid="ref6">6, 8</xref>
          ]. There was a total of nine students, 2 researchers, and 1 teacher involved
in the study (Table 1). The learning activity was prepared in advance by a researcher and
the subject teacher. The data collected from this study was used to study the feasibility of
automating collaboration quality estimation [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] and to gain insights into the teacher’s perception
regarding the utility of MMLA for monitoring collaborative learning in the classroom [12].
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. Iteration-2: Using CoTrack</title>
        <p>In our next iteration (Figure 2), we developed a web-based application called CoTrack2 to simplify
the use of multimodal data collection in f2f and to also make it possible in online learning
settings [13, 16]. With the development of CoTrack, we automated all the steps which needed
1Etherpad is a real-time collaborative text editor.
2https://www.cotrack.website
manual setup in the first prototype (i.e., time synchronization, and feature pre-processing). In
our second iteration, the study involved 174 students from 4 diferent schools, 9 diferent subject
teachers, and 2 researchers (Table 1) [13]. The data from this study was used for developing
automated collaboration estimation models for building intervention guiding tools.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Challenges faced while conducting MMLA research in classroom settings and potential solutions</title>
      <p>Here, we outline the main challenges we faced during the enactment of our MMLA research in
the classroom setting.
#1. Technical expertise was needed to set up the first prototype to collect multimodal
educational data.</p>
      <p>The first challenge we faced was associated with the technological complexities inherent in
MMLA. The developed prototype in the first iteration required a particular setup with a specific
set of commands (e.g., running an MQTT server, starting Raspberry Pi devices, setting up an
ad-hoc network, and configuring time synchronization). Thus, there was a need for a person
with technical expertise whenever the prototype was used, resulting in data collection from
fewer classroom sessions.</p>
      <p>Solution: We addressed this challenge by automating most of the technological
configuration steps. It resulted in a prototype (iteration-2) with an easy-to-use interface without the need
for technical expertise which was needed in the first version of the prototype. The prototype
allowed teachers to create collaborative learning activities with multimodal data capturing and
monitoring functionality without the need for a technical expert. Another potential solution
could be to use a fixed MMLA setup that is already configured in a classroom.</p>
      <p>#2. The prototype used in classroom settings caused obtrusiveness in the learning
process.</p>
      <p>The prototype’s usage from the first iteration required a preliminary set-up phase which caused
interruptions in the classroom. During the study, the setup took an additional time of (10-15
minutes) before starting the learning activity. Moreover, during the activity, the researchers
present in the classroom were ensuring the device’s functioning which most likely distracted
students’ attention.</p>
      <p>Solution: We minimized the obtrusiveness by using a minimal number of devices for data
collection purposes. We used the laptop’s microphone and video camera for data collection
purposes.</p>
      <p>#3. Covid-19 restrictions complicated the situation further.</p>
      <p>The arrival of the pandemic Covid-19 put restrictions on physical participation in Estonian
schools which closed all possibilities of using the developed prototype (version-1) in classroom
settings for multimodal data collection.</p>
      <p>Solution: We tackled this challenge in our second iteration by transforming our raspberry
pi-based prototype into a complete web-based application. This feature allowed us to collect
more data in our second iteration of the study. Furthermore, this also enabled researchers
without technical expertise to use multimodal data-capturing functionality in their research.</p>
      <p>#4. An increased number of requests sent for storing extracted multimodal features
exhausted the server’s resources.</p>
      <p>As we had integrated Voice Activity Detection (VAD) and Speech-to-Text in CoTrack, it increased
the number of requests received on the server. Furthermore, CoTrack also stores media files
(e.g., audio and video) that need a larger space on the server. These posed the issue of scalability.
Solution: We are now exploring cloud-based solution to store our multimodal data and deal
with the challenge of server resource exhaustion.</p>
      <p>#5. Students found it dificult to follow MMLA-related instructions along with
learning activities.</p>
      <p>Though we simplified the use of CoTrack in comparison with the Raspberry Pi-based prototype,
there were still a few instructions for students to follow while using CoTrack. For example, one
instruction was to click on the finish button once the learning activity is done which saved the
ifnal audio (or video) file on the server. However, during our data collection, we observed many
instances when students simply closed the application without clicking on the finish button
which caused a loss of audio/video data.</p>
      <p>Solution: This challenge made us realize the need for the MMLA tool with minimal reliance
on students for any data collection-related controls. We are now aiming to eliminate this
requirement by simply saving media files (audio/video) in the background when students leave
the learning activity space in CoTrack.</p>
      <p>#6. Multimodal data collection had a lower quality of data due to the noisy settings
of the classroom.</p>
      <p>Multimodal data collected from classroom settings are most likely to be of a lower quality than
data collected from a controlled setting. For example, in the case of face-to-face group activity
where participants sit close to each other, the chances of audio data getting corrupted become
higher.</p>
      <p>Solution: The data from classroom settings is most likely to have noise, thus, there should be a
mechanism to deal with that noise or we should employ data analysis (or modeling) techniques
which are noise resistance. In this direction, the next step could be to first understand how the
presence of noise in data afects results from analysis or modeling. Another potential idea to
deal with noisy data is to exploit cross-modal features. For example, speaking time extracted
from audio data can be corrupted as a result of loud noises in the classroom; here, we can extract
the same feature also from video using computer vision (e.g., lip-activity detection [17]) and
then utilize it in a complementary way.
#7. Issue of variation in learning contexts on multiple aspects.</p>
      <p>The learning contexts from where the datasets were collected varied on multiple aspects, e.g.,
schools, subjects, educational level, communication language, teacher, etc. This raised our
concern over the applicability of analysis results to a broader context.</p>
      <p>Solution: To deal with this challenge of context variance, broader data gathering in multiple
learning contexts is needed which could further enable a stricter evaluation of the generalizability
of analysis results, e.g., across contexts evaluation [8, 13].
#8. Complexity of multimodal data visualization.</p>
      <p>During our initial phases of prototype development, we involved teachers in the design phase
[18]. Teachers reported having freedom in selecting what analytics to see rather than having all
the data plotted for them. In addition, they also suggested having some abstract representation
for the group’s participation or to show collaboration quality levels.</p>
      <p>Solution: We addressed this challenge by incorporating teachers’ suggestions in our current
version of CoTrack. We now plan to investigate teachers’ perspectives on the usefulness of
CoTrack in monitoring and guiding collaborative learning activities in the classroom.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Discussion</title>
      <p>This paper shares our experience of conducting MMLA research in classroom settings in terms
of the challenges faced and how we handled them. We also presented some open challenges
(e.g., noisy data from the classroom) with some ideas on their potential solution. We like to
mention that our solutions are the result of general engineering and are not MMLA-specific.
Some solutions (e.g., for #5) can be related to already existing design guidelines for edTech, e.g.,
minimalism principle for classroom orchestration [19].</p>
      <p>In the workshop, how other MMLA researchers have solved challenges in authentic settings
could be discussed. The knowledge from the such discussion could result in a manual or tutorial
about applying MMLA in authentic settings which we hope can help researchers to conduct
MMLA studies in authentic settings.
oration? A review of the empirical links between multimodal metrics and collaborative
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Efar-mmla: An evaluation framework to assess and report generalizability of machine
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[11] A. Kharrufa, M. Balaam, P. Heslop, D. Leat, P. Dolan, P. Olivier, Tables in the wild: Lessons
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