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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Evaluating the AFEL Learning Tool: Didactalia Users' Experiences with Personalized Recommendations and Interactive Visualizations</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Seren Yenikent</string-name>
          <email>s.yenikent@iwm-tuebingen.de</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Peter Holtz</string-name>
          <email>p.holtz@iwm-tuebingen.de</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stefan Thalmann</string-name>
          <email>sthalmann@know-center.at</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mathieu d'Aquin</string-name>
          <email>mathieu.daquin@insight-centre.org</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Joachim Kimmerle</string-name>
          <email>j.kimmerle@iwm-tuebingen.de</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Insight Centre for Data Analytics, National University of Ireland</institution>
          ,
          <addr-line>Galway</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Know-Center Graz;</institution>
          <addr-line>Inffeldgasse 13, 8010 Graz</addr-line>
          ,
          <country country="AT">Austria</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Leibniz-Institut für Wissensmedien (IWM)</institution>
          ,
          <addr-line>Schleichstr. 6, 72076 Tübingen</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Learning technologies offer opportunities for users to enhance and to personalize selfregulated learning activities. In this paper, we present the results of a laboratory study that covers the user evaluation of the AFEL Didactalia app, which analyzes everyday learning activities of learners, extracts learning scopes and trajectories, and provides personalized recommendations of learning resources as well as an interactive visualization of learning activities. Participants of the study (N=76) engaged with the tool after first completing an assigned learning task related to geography or history using learning materials from the Didactalia platform for approximately 30 minutes and afterwards freely exploring the platform for 30-45 minutes. The related behavior data was tracked and analyzed by the AFEL learning tool. After completing the two tasks, participants received an introduction to the tool and explored them as well. The results suggest a satisfactory experience with the tool and provide insights on the potential benefits, as well as aspects to be improved for further development. We discuss our findings and the next steps of the investigation in detail.</p>
      </abstract>
      <kwd-group>
        <kwd>learning analytics</kwd>
        <kwd>mobile learning</kwd>
        <kwd>user experience</kwd>
        <kwd>technology-enhanced learning</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        This study presents the first part of a more comprehensive ongoing investigation that
aims to understand the nature of everyday learning and the effectiveness of the AFEL
(Analytics for Everyday Learning) tool in particular. For this purpose, we obtained
feedback from users in a controlled laboratory environment. The main purpose of the
project is to understand the potential benefits of tools supporting analytics for everyday
learning by taking human dimension as well as design factors (i.e., content, technology)
and social factors (e.g., social norms) into account [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
1.1
      </p>
    </sec>
    <sec id="sec-2">
      <title>AFEL Learning Tool</title>
      <p>
        AFEL - Analytics for Everyday Learning is a project funded by the EU research and
innovation program Horizon 2020 that aims to device methods and tool to understand
and improve informal online learning (http://afel-project.eu). Within the present study,
we had users evaluate the version of the AFEL tool that was specifically customized
and adapted for the Didactalia platform (http://didactalia.net/), which is run by the
Spanish company GNOSS, one of the partners in the AFEL consortium. Didactalia is a
collection of more than 100.000 educational resources, such as web pages, slides, or
interactive maps as well as educational games. Most of the materials are in Spanish
language, but there is a substantial amount of English language resources as well.
Didactalia also provides some social media functionalities, such as forums and groups
to its users. The AFEL Didactalia App monitors all activities of a given learner on the
platform and extracts, for example, learning scopes and trajectories [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. In consequence,
it provides personalized recommendations and an interactive visualization of the
learner’s activities. The main goal of the personalized recommendation function is to
provide learners with user-based resources grounded in their interactions with the
content. The visualization tool, on the other hand, enables personalized data exploration
for the learners by offering various visualization aids, such as bar charts and plots. In
the present study, we wanted to have users spend a sufficient amount of time within a
controlled laboratory environment as means of generating enough data for the AFEL
Didactalia App to demonstrate the aforementioned functionalities (personalized
recommendation and interactive visualization) so that the learners can evaluate their
usefulness.
      </p>
      <p>
        Apart from evaluation purposes, the study was also used to relate certain forms of
searching behavior to knowledge outcomes that were measured using standardized
knowledge tests which had already been used in earlier studies using participants who
were recruited from crowd-working platforms [3; 9]. The present study allowed for
studying ‘(online) Search as Learning’ [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] processes in a controlled laboratory
environment by means of combining questionnaire data, behavioral data, and data from
knowledge tests. However, the present summary of the study focuses merely on the
evaluation results of the AFEL Didactalia App’s recommendation and visualization
functions.
1.2
      </p>
    </sec>
    <sec id="sec-3">
      <title>Technology Acceptance Model</title>
      <p>
        The theoretical foundation of the evaluation study is based on the Technology
Acceptance Model [TAM; 8] that explains the process of accepting a new technology
by highlighting the influence of several interrelated dimensions: external factors (e.g.,
system characteristics), cognitive responses (e.g., technological self-efficacy), as well
as social factors (e.g., behavioral norms) lead to intermediary factors, such as perceived
usefulness, perceived ease of use, and attitudes toward the technology, which in turn
predict intentions to use the technology in the future. We used a specific adaptation of
the TAM [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] for the e-learning context (see Method section for detailed information).
      </p>
      <p>
        Previous research has shown the impact of user perception on improving learning
analytics tools. For instance, [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] analyzed forum discussions of an online university
and demonstrated that technology acceptance factors, such as intentions and
community factors, played important roles in virtual academic environments. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]
suggested that a user-centered evaluation method is necessary to understand how users
feel when they engage with visualization systems. User perception is also essential in
designing recommender applications. Apart from accuracy and quality of the content,
it has been shown that usability of a system and learners’ attitudinal and behavioral
intentions are important features that influence systems’ evaluations [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. These studies
support that approaches, which take learner needs into careful consideration and design
the systems accordingly in order to offer appropriate activities and assessments for the
learners, are likely to lead to deep learning [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Further research on evaluating learning
technology in informal learning situations and across contexts requires a profound
understanding of the user needs [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. Our study extends such research that emphasizes
user experiences in evaluating and designing tools for learning analytics by adopting
an experimental approach based on a sound theoretical basis.
2
2.1
      </p>
      <sec id="sec-3-1">
        <title>Method</title>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Participants</title>
      <p>Participants were recruited via an online participant tool that mainly consisted of
university students. Participants were invited to the laboratory. In total, we had 76
English-speaking participants (54 female; average age=23.95y; median=22 y).
2.2</p>
    </sec>
    <sec id="sec-5">
      <title>Material</title>
      <p>
        The questionnaire for the evaluation of the experience of using Didactalia for learning
tasks with the help of the AFEL Didactalia App consisted of three sections:
General evaluation. The general evaluation section was adapted from a previous study
on the evaluation of software products [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], and comprised of the following dimensions
that were derived from the aforementioned TAM: Perceived usefulness of the software,
perceived ease of use, attitudes toward using the software, the behavioral intention,
subjective norms, technological self-efficacy, and system accessibility. Each of these
dimensions was measured with three items except for attitudes toward using the app
(two items) and system accessibility (one item). The internal consistency (Cronbach’s
Alpha) of these subscales ranged from α=.69 (subjective norms) to α=.93 (behavioral
intention). All items were answered on a seven-point Likert scale ranging from 1 = not
at all to 7 = yes, definitely.
      </p>
    </sec>
    <sec id="sec-6">
      <title>Evaluation of the recommendation function. Participants answered five evaluation</title>
      <p>questions with regard to the recommended learning resources, also using a seven point
Likert scale. The items addressed their actual usage of the function (I have checked out
most of the recommended learning resources), usefulness of the function (The
recommended learning resources were useful for me), novelty (The recommended
learning resources were novel to me), difficulty (The recommended learning resources
were too difficult for me), and the topic coverage (The recommended learning resources
were covered many different relevant areas). Participant also answered one open
question (What did you miss in the recommendations?).</p>
      <p>Evaluation of the visualization function. Participants answered three Likert-type
questions with regard to the visualization functionalities of the app. They were asked
to indicate their usage of the function (I have tried out the app’s interactive
visualization functions), usefulness (The visualizations were useful for me), difficulty of the
function (It was very difficult to use the visualizations) along with one open question
(What did you miss in the visualizations?)
2.3</p>
    </sec>
    <sec id="sec-7">
      <title>Procedure</title>
      <p>The study took place in a laboratory with computers provided to each participant in a
cubicle. At the beginning, every participant received extensive information regarding
the scope and background of the study as well as data storage and data management
issues and other legal aspects. Afterwards, participants provided their written informed
consent and received an information sheet detailing their tasks. First, participants were
assigned to either the geography or the history learning task (38 participants each).
Afterwards, they filled in the respective online knowledge test for the first time. Then,
participants spent 30-40 minutes looking for information regarding their learning topic
on the Didactalia platform after registering to the platform using a prefabricated
IDcode. After finishing their learning task, they answered the knowledge test for the
second time. In the next step, participants were asked to spend 30-45 minutes freely
exploring Didactalia. Finally, they were introduced by the examiner to the AFEL
Didactalia App and received a 2-page leaflet explaining the app. After spending 5-10
minutes exploring the app, they answered the evaluation questions. Participants
received a financial compensation of 16€ for two hours of work.</p>
      <p>In addition to the questionnaire data, behavior data during the use of Didactalia and
the mobile application was captured in order to gather information on what resources,
searches and features the users have been engaged with. We also collected data in the
forms of pre- and post-knowledge tests to assess the actual learning after using the
learning tool. This data will be analyzed in the next steps of the investigation.
3</p>
      <sec id="sec-7-1">
        <title>Results</title>
        <p>In this section we present the findings of the general evaluation of the app as well as
the evaluation of the recommendation and visualization functions.
3.1</p>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>3. 1 General evaluation of the app based on TAM</title>
      <p>We first scrutinized participants’ responses to the general evaluation questionnaire
based on the psychometric dimensions of the scale. In particular, easiness (M=4.08,
SD=1.45) and accessibility of the app (M=4.76, SD=1.76) were among the top rated
features. Participants reported a comparatively high level of technological self-efficacy
(M=4.85, SD=1.37). The ratings for perceived usefulness (M=3.69, SD=1.74), attitudes
(M=3.48, SD=1.47), and subjective norms (M=3.87, SD=1.37) were also above the
scale midpoint. Although these six subscales were somehow satisfactorily rated,
behavioral intention to use the app in the future (M=2.57, SD=1.45) was the lowest
among the seven subscales. However, according to a Kolmogorov-Smirnov test
behavioral intention was neither for the history, D(37)=0.15, p&lt;.05, nor for the
geography condition, D(38)=0.22, p&lt;.001, normally distributed. Visual inspection of
the distribution of scores indicated in both cases a bimodal distribution: Whereas a
majority of users did not intend to use the app in the future, there was in both cases a
minority that indeed intended to use the app (see Fig. 1). Additionally, we compared
the geography and the history groups in terms of the ratings they reported for each
subscale. No significant differences were observed between the groups. Fig. 2 displays
the mean results as well as the t and p values.</p>
    </sec>
    <sec id="sec-9">
      <title>Evaluation of the recommendation function</title>
      <p>The learners’ responses to the items for the evaluation of the recommendations were in
all cases slightly above the scale midpoint. Participants reported an above midscale use
of the recommended sources (M=3.79, SD=1.60). The recommendation function was
found moderately useful (M=3.95, SD=1.55) and novel (M=3.91, SD=1.42), and not
too difficult (M=2.45, SD=0.97). Diversity of the topics covered were rated as fairly
high (M=4.15, SD=1.63). In total, 45 participants answered the open question (What
did you miss in the recommendations?). What they missed in general were English
sources, more relevant sources to the assigned learning topic, and more
diverse topics including other disciplines. These experiences might have kept
participants from further utilization of the recommended resources and may be the reason for
the moderate use of the function. Comparing the two learning topics (geography and
history), we found a significant difference with regard to the use of the recommendation
function, t(71)=3.95, p&lt;.001. Learners in the history group reported more usage
(M=4.46, SD=1.36) than those in the geography group (M=3.11, SD = 1.54). There were
no significant differences regarding the other features. Fig. 3 shows the general
tendencies of the two groups.
3.3</p>
    </sec>
    <sec id="sec-10">
      <title>Evaluation of the visualization function</title>
      <p>Participants reported an above mid-point use of the visualization function (M=4.85,
SD=2.04), which reflects that they were instructed explicitly to try out the interactive
visualization. Although reported difficulty (M=4.84, SD=1.78) was relatively higher
than in case of the recommendations, the visualization function was still rated as fairly
useful (M=4.11, SD=1.92). 47 participants indicated their opinion on what they missed
in the visualizations. Apart from structural features such as colors, bigger and more
detailed illustrations, participants reported to have missed more diverse topics, more
specific information on the searched topics and information on how to use the function.
There was no significant difference between the ratings of geography group (M=4.86,
SD=2.17) and the history group (M=4.84, SD=1.93) in terms of the use of the
visualization function, t(73)=0.04, p=.96. The groups’ responses did not differ for the rest of
the features either (see Fig. 3).
4</p>
      <sec id="sec-10-1">
        <title>Conclusion</title>
        <p>
          Overall, the presented results provide insights on the strong aspects of the app as well
as the aspects that need further improvement. In general, the evaluation of our app could
be considered as satisfactory especially in terms of easiness, accessibility, usefulness,
and compatibility with the subjective norms. The recommendations and the interactive
visualization were also rated satisfactorily. The only statistical difference between the
learning topics was observed for the learners’ in the history and the geography groups
in terms of the utilization of the recommendations; here, participants in the history
condition indicated a higher use of recommendation sources. The lack of statistically
significant differences between the two conditions with regard to other ratings of the
recommendation and visualization features indicates that the app could address
different types of learning scopes. In spite of such fairly high ratings of the app features,
participants were on average not very much willing to use the app in the future. This
result is not in line with previous research that demonstrated effects of user satisfaction
on usage behavior [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ], and gets even more remarkable considering that our participants’
perceived tech-savviness was quite high. It should be noted though that we found a
bimodal distribution of the intention-to-use scores indicating that whereas a majority of
participants is not interested in the app, a minority nevertheless intends to use it in the
future. One potential reason could be related to most users’ habit of using mobile apps
for non-instructional purposes (e.g., texting, looking up simple information such as
events). Thus, many users may not completely be aware of the benefits of such
technology for learning purposes even though they acknowledge the usefulness of
mobile learning apps [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ].
        </p>
        <p>7
5
3
1
t=-1.05
p=.29
t=-.40
p=.68
4.14
3.76
3.84
3.97
t=1.95
p=.05</p>
        <p>
          The presented findings are based only on self-reports. In the next steps, we will
utilize the behavioral data that was tracked during the plug-in and compare the aspects
of the perceived usage and the actual usage to get a more accurate grasp of the learners’
interaction with the app [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ]. The results of the knowledge tests will also provide a better
understanding on to what extent the AFEL app could be used to enhance learning.
        </p>
      </sec>
      <sec id="sec-10-2">
        <title>Acknowledgement</title>
        <p>The project “AFEL – Analytics for Everyday Learning” is funded under the Horizon
2020 of the European Commission (project number GA687916). The Know-Center is
funded within the Austrian COMET Program - Competence Centers for Excellent
Technologies - under the auspices of the Austrian Federal Ministry of Transport,
Innovation and Technology, the Austrian Federal Ministry of Economy, Family and Youth.</p>
      </sec>
    </sec>
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