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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Exploring Inquiry-Based Learning Analytics through Interactive Surfaces</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Sven Charleer, Joris Klerkx, and Erik Duval Dept. of Computer Science KU Leuven Celestijnenlaan 200A 3001 Leuven</institution>
          ,
          <country country="BE">Belgium</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Learning Analytics is about collecting traces that learners leave behind and using those traces to improve learning. Dashboard applications can visualize these traces to present learners and teachers with useful information. The work in this paper is based on traces from an inquiry-based learning (IBL) environment, where learners create hypotheses, discuss ndings and collect data in the eld using mobile devices. We present a work-in-progress that enables teachers and learners to gather around an interactive tabletop to explore the abundance of learning traces an IBL environment generates, and help collaboratively make sense of them, so as to facilitate insights.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;interactive surfaces</kwd>
        <kwd>learning analytics</kwd>
        <kwd>learning dashboards</kwd>
        <kwd>collaboration</kwd>
        <kwd>re ection</kwd>
        <kwd>awareness</kwd>
        <kwd>information visualization</kwd>
        <kwd>sense-making</kwd>
        <kwd>inquiry-based learning</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>
        Similar to the Quanti ed Self 1 movement, which focuses on
collecting user traces and using the data for self-improvement,
Learning Analytics can help to understand and optimize
(human) learning and the environments in which it occurs [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ].
However, capturing learner traces can generate an
abundance of data, especially in the context of Massive Open
Online Courses (MOOCs) that involve tens to thousands of
learners whose activities can be tracked in detail. Re
ecting on those traces can help learners to understand what is
the optimal setting and context in which they learn best.
Teachers can, among other things, use the same traces to
nd out where learners struggle with what content or
activity. Dashboards help present this abundance of data in a
way that supports both teachers and learners [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ].
Teachers show interest in using dashboards collaboratively
with learners to discuss their activities, progress and
results [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Interactive tabletops can facilitate and capture
collaboration activities in the classroom [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. In previous
work [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] we explored this platform to visualize learning
analytics data (see Figure 1), using the a ordances (e.g. large
display size, multi-user interaction) of interactive tabletops
to create a collaborative sense-making environment [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
This paper describes our work-in-progress on an interactive
tabletop visualization for learner traces that are generated
by students in an inquiry-based learning (IBL) environment.
Section 2 brie y present the learning environment and the
data it generates. Section 3 discusses development details,
section 4 explains the design of the tabletop visualization.
We discuss our ndings and future work in section 5
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. IBL LEARNING TRACES</title>
      <p>
        Contrary to a traditional passive role in a classroom, in
Inquiry-Based Learning (IBL), learners assume an active
role as explorer and scientist with a focus on learning \how
to learn". Teachers try to stimulate learners to pose
questions and create hypotheses regarding a speci c topic,
perform independent investigations, gather data to con rm and
discuss their ndings and generate conclusions. 6 phases
of learning activities are often discerned in an IBL process
model: problem identi cation, operationalization, data
collection, data analysis, interpretation and communication [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
As each learner can follow his own route through the IBL
process, it is obvious that the sequence and length of these
phases di er among students. Individual and collaborative
re ection is furthermore vital in every phase. Indeed,\even
at the very beginning when students need to develop a
question or a hypothesis, they need to re ect upon the question,
and evaluate it before they decide to proceed. They also need
to re ect while deciding what kind of data they need to
collect, how to proceed to data analysis, and how to
communicate their results" [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
      <p>In the weSPOT Inquiry Environment 2, a teacher can set
up an inquiry regarding a speci c research topic. For each
phase, learners can use a set of widgets (see Figure 2) to
e.g. create hypotheses, ask questions, rate and comment
on activities, generate mind-maps, etc. By taking pictures,
recording videos, entering text and data from measurements
through a mobile application, students collect data in the
eld to support their hypotheses. All activities in the
learning environment are logged and stored in a data store and
exposed as learning traces through REST services.
Teachers and students can access the learning analytics data of a
speci c inquiry through a web-based dashboard integrated
in weSPOT Inquiry Environment 4, and the tabletop
application.</p>
    </sec>
    <sec id="sec-3">
      <title>3. ITERATIVE DEVELOPMENT</title>
      <sec id="sec-3-1">
        <title>2http://inquiry.wespot.net/</title>
        <p>Following a user-centered rapid prototyping approach, we
started from paper prototypes to gather initial feedback on
early ideas, gradually developed more functional digital
prototypes which have been deployed and evaluated with
learners regarding usability.</p>
        <p>Web technologies (HTML, CSS3 and JavaScript) facilitate
development of quick prototypes and allows us to deploy
on most school infrastructures. Interaction is supported
through both native browser mouse/touch events and the
npTUIClient plug-in 3, allowing the application to run on
interactive tabletops, interactive white-boards, tablets, phones
and desktop computers. Our interactive tabletop setup
currently facilitates up to 5 users.</p>
        <p>A centralized lter system using Cross lter 4 and a modular
and event-based architecture facilitates easy creation of new
widgets. D3.js 5 and Processing.js 6 help visualize the data.
A Node.js 7 back-end generates the web pages while fetching
the learning traces from the weSPOT environment.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. DESIGN</title>
      <p>
        Flexible visual analysis tools must provide appropriate
controls for specifying the data and views of interest [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
Filtering out unrelated information to focus on relevant items is
the key control in our learning dashboards due to the
abundance of traces learners leave behind. Previous work [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] has
shown that there is also a need for context and content to
complement the visualized data. We therefore follow the
visual information-seeking mantra of \Overview rst, zoom
and lter, then details-on-demand" [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]: our tabletop
visualization presents users with a coordinated set of widgets
which contain: (i) a complete overview of all activities
(Figure 4.A), (ii) data lters (Figure 4.B/D) and (iii) the content
view (Figure 4.C).
      </p>
      <sec id="sec-4-1">
        <title>3https://github.com/fajran/npTuioClient</title>
        <p>4http://square.github.io/crossfilter/
5http://d3js.org
6http://processingjs.org
7http://nodejs.org</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>4.1 Visualizing IBL Traces</title>
      <p>The visualization displays a time-line per activity thread (see
Figure 5). For instance, the creation of a hypothesis by a
learner is followed by every comment on, rating on, and edit
of the hypothesis. Squares represent create and edit events,
while circles represent comment events. Stars represent a
rating activity, triangles are data collection events.
Activities within a single thread are connected by a horizontal
line. This enables teachers and learners to see the evolution
of an activity thread, the comments that may have impacted
edits of e.g. the original hypothesis, and the rating trend.
Activities in other activity threads can enrich the context
of a speci c thread. A discussion in one thread might
inuence the creation of a new hypothesis, or an edit of an
existing one. Therefore, every activity is positioned relative
in time to all other activities displayed, allowing the users
to backtrack through time across multiple threads at once
(see Figure 6.A).</p>
      <p>IBL phases (see Section 2) in which an activity occurs are
indicated by di erent background colors, matching the colors
used of the web dashboard (see Figure 4). The
visualization can be panned and zoomed using standard multi-touch
interactions.</p>
    </sec>
    <sec id="sec-6">
      <title>4.2 Filtering the Data</title>
      <p>Using the lter widgets, users can focus on activities by
drilling down on one or more phases (see Figure 4.D), or one
or more learners (see Figure 4.B). When multiple learners
are selected (e.g. a group that works together), the path of
each learner can be individually highlighted (see Figure 6.B),
in order to provide an overview of work distribution. This
can help teachers to nd struggling learners in a group. It
can also help learners to become aware of uneven work
distribution and help to redivide the work. The path can also
shed light on the methodology a learner uses to reach a
certain result (e.g. Figure 4.A).</p>
      <p>
        The interface of Figure 4 is limited to one person driving
the navigation and only supports global lters. To fully
use the a ordances of the tabletop and create a
collaborative sense-making environment, the application must
support both individual as well as group work [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Figure 7
shows an early prototype that presents 5 participants with
individual ltering tools. Global lters result in more tightly
coupled collaboration [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], but can disturb individual work.
One participant's lter activity could remove data from the
visualization another participant is working with. To allow
participants to simultaneously lter the data presented on
the tabletop, we use the multivariate attributes of a
glyphbased visualization [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. The lter result of each participant is
highlighted in the color corresponding to the user interface.
      </p>
    </sec>
    <sec id="sec-7">
      <title>5. CONCLUSION AND FUTURE WORK</title>
      <p>Our interactive visualization will be deployed in multiple
secondary school pilots 8 across Europe, both on
interactive tabletop devices and interactive white-boards.
Questionnaires regarding usefulness for both teachers and
students will help evaluate our design choices, while interaction
logging and video recordings of collaboration sessions can
provide insights in whether the application is useful as a
sense-making environment.</p>
      <p>Our application lets users retrace individual steps taken by
(groups of) learner(s), i.e. they can collaboratively (i)
re8http://portal.ou.nl/web/wespot/pilots
ect on the rationale of a learner's decisions and actions,
(ii) (re-)examine past explanations and conclusions, and (iii)
(re-)evaluate past evidence data. Students can learn from
peers' activities through exploration, discovery and
discussion. The application can be used for evaluation purposes,
allowing (groups of) learner(s) and teacher(s) to iterate over
every step performed from hypothesis to conclusion together.
Pilot data can also help IBL researchers with the discussion
and re nement of the IBL model.</p>
      <p>
        Enabling multiple learners and teachers to interact with the
visualization simultaneously remains the biggest challenge.
We shall further explore the possibilities of glyph-based
visualizations to provide unobtrusive global lters, use user
position tracking through technology such as Kinect to
support the dynamic nature of collaborators around a tabletop
and explore data lenses (e.g. GeoLens [
        <xref ref-type="bibr" rid="ref15 ref7">15, 7</xref>
        ]) to facilitate
individual exploration of the data on a shared visualization.
      </p>
    </sec>
    <sec id="sec-8">
      <title>6. ACKNOWLEDGMENTS</title>
      <p>The research leading to these results has received funding
from the European Community's Seventh Framework
Programme (FP7/2007-2013) under grant agreement No 318499
- weSPOT project.</p>
    </sec>
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