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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Reflection support using multi-encoded Tag-clouds</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Christian Glahn</string-name>
          <email>christian.glahn@ou.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marcus Specht</string-name>
          <email>marcus.specht@ou.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rob Koper</string-name>
          <email>rob.koper@ou.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>OTEC, Open University of the Netherlands</institution>
          ,
          <addr-line>Valkenburger Weg 177, 6411AT Heerlen</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
      </contrib-group>
      <fpage>89</fpage>
      <lpage>97</lpage>
      <abstract>
        <p>This paper reports on a qualitative study about the application of tag clouds for supporting meta-cognition in self-directed and incidental learning. It analyses the use of a personal tag-cloud visualization of the tags that are used at a public social bookmarking service. The study focuses at the types of metacognitive control based on reflection notes of the learners. These notes were analyzed regarding the contents of the reflections as well as regarding their meta-cognitive type. The study has two important outcomes. Firstly, a personal tag cloud can stimulate reflection on the tagging activity of a learner. Secondly, reflecting on the tagging activity is not built into the design of a tag cloud.</p>
      </abstract>
      <kwd-group>
        <kwd>tagging</kwd>
        <kwd>visualization</kwd>
        <kwd>evaluation</kwd>
        <kwd>reflection</kwd>
        <kwd>self-directed learning</kwd>
        <kwd>incidental learning</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        This paper focuses on tag clouds that are based on the personal tagging information of
a learner. For supporting self-directed and incidental learning tag clouds hold some
potential to stimulate reflection on concepts and learning processes, even though such
visualisations do not show valid information in terms of approved domain knowledge.
A tag cloud can stimulate reflection because the visible tags are meaningful to the
learner and allow associations to the actual learning experiences. This paper reports
on a qualitative study about using tagging visualisations to stimulate reflection about
self-directed or incidental learning activities. This article analyses if the visualisation
of a learner's tagging activity in the form of a tag cloud can stimulate meta-cognition
of self-organised learners. The present study analyses the types of reflection that are
stimulated by a personal tag cloud that is based on a mash-up of different information
that is provided by the social bookmarking service delicious.com [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
Tagging stands for applying free form keywords (the tags) to resources that result in
user-generated metadata. Tagging is closely related to the developments in the context
of the Web2.0 [19]. A number of scientific contributions focus on tagging as a type of
user and community driven creation of meta-data [
        <xref ref-type="bibr" rid="ref10 ref11">10, 11</xref>
        ], or used tags to improve the
accessibility of contents [
        <xref ref-type="bibr" rid="ref12">12, 19</xref>
        ]. A number of commercial Web2.0 services supports
tagging, because freeform tags provide an easy and flexible way for organizing
content and information.
      </p>
      <p>
        Prior research [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] has argued that labelling and tagging supports meta-cognitive
processes in self-regulated learning. Several studies [
        <xref ref-type="bibr" rid="ref1 ref18 ref2">1, 2, 18</xref>
        ] analyzed visualizations
of conceptual structures for supporting self-regulated learning in pre-structured
knowledge domains. Therefore, the designs of the visualizations were guided by the
external learning objectives of the related formal educational context. In these settings
the learners could not extend the tagging vocabulary or the conceptual structures.
      </p>
      <p>
        In contrast to formal education, self-directed learning is defined by a high degree
of learner control in weakly structured knowledge domains [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. This idea of learner
control is already incorporated with many Web2.0 services that enable their users to
create personal concept structures through tagging rather than replicating predefined
concept structures [21]. This has inspired the development of personal learning
environments [24].
      </p>
      <p>
        The concept structures in personal learning environments vary for each user and
can range from a few tags to a couple of hundreds. This freedom for the learners
requires that visualizations are independently designed from conceptual structures or
knowledge domains. Related approaches [
        <xref ref-type="bibr" rid="ref13 ref4">4, 13</xref>
        ] visualize learner actions that were
monitored by the supporting system – the “interaction footprints” [23].
      </p>
      <p>
        The present paper analyses if tag clouds can stimulate and support reflection in
self-directed and incidental learning, which depends on the ability to reflect on actions
[
        <xref ref-type="bibr" rid="ref5">5, 20</xref>
        ]. Three variations of reflection were identified to be relevant for learning:
reflection on action, reflection in action, and reflection for action. The main difference
of these reflection types is the occurrence of the reflection. Ertmer &amp; Newby [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]
define reflection as an activity that links meta-cognitive knowledge and
metacognitive control (self-regulation). The related reflective processes can be clustered
into three stages: planning, monitoring, and evaluating.
      </p>
      <p>
        Lave &amp; Wenger [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] introduced the concept of situated learning. This concept
reflects the social dimension of learning. From this perspective learning cannot be
reduced to a set of learning events, but requires tight coupling to the related social
practices. Further studies highlighted several dimensions and factors of
contextualization in learning [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] and contextual support for learning [22]. Table 1
shows the relation between these dimensions and factors. This relation allows
identifying, which types of interpretations of the learning processes can be expected
for a context dimension. This study focuses at the level of process and concept as the
primary context dimensions.
3
      </p>
    </sec>
    <sec id="sec-2">
      <title>ReScope</title>
      <p>
        The present study uses the ReScope system [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. ReScope is a web-based mash-up for
fetching, aggregating, and visualising tagging activities in the social bookmarking
service delicious.com [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] and allows learners to annotate and to track their tagging
activities. ReScope has provides two tools: a tag cloud visualisation and a tag cloud
annotation tool. The ReScope tag cloud provides different perspectives on tagging by
combining and contrasting different aspects of tag usage through colour codes and
font sizes. With tag cloud annotation learners can track their tag clouds over time: as
soon as an annotation is submitted, a snapshot of the current tag cloud is attached to
it. When a user clicks at an older annotation, the attached tag cloud is loaded and
displayed to the learner. Figure 1 shows an example of the ReScope user interface.
      </p>
      <p>The design of the ReScope tag cloud is based on the contextual dimensions
concept and process of the contextualization dimensions of situated learning.
1. Concepts: The overall tag usage of each tag is indicated by its font-size.
2. Process: The most recent usage of tags is indicated through color codes.</p>
      <p>Because this information is entirely based on the tags that are used by a learner, it
is expected that it can serve as an anchor for reflecting about the personal tagging
habits and the related knowledge structures.
4</p>
    </sec>
    <sec id="sec-3">
      <title>Research objectives and questions</title>
      <p>This study has two main objectives: (a) identify if and how tag clouds can stimulate
meta-cognition of learners regarding their self-directed and incidental learning on the
Web2.0; and (b) identify design factors for the underlying use case for reflection
support. Within this scope this study addresses the following questions.
─ Does the ReScope tag cloud stimulate meta-cognitive activity?
─ Does the reflection on the tag cloud confirm contextual factors suggested by the
contextual framework for situated learning?</p>
      <p>According to the relations of contextual dimensions and factors, it is expected that
the notes can be linked to the context factors rhythm, value, and connection. Rhythm
refers to all types of structuring a process. Value covers anything that is related to the
added value of concepts and conceptual structures for the learner. The factor
connection refers to the structure of the concepts as well as the relation of concepts to
resources. The factors “integration” and “community building” are not expected to
occur, because ReScope does not visualize connections between peers.
5</p>
    </sec>
    <sec id="sec-4">
      <title>Method</title>
      <p>The participants were invited through promoted on several mailing lists, web-logs,
web-sites of related research projects, and on two European conferences in the
domain of computer assisted learning. The participation was entirely voluntarily. The
interface of the ReScope system included information texts that asked the participants
to write down their thoughts about their reception of the tag cloud in the notes field
and to label important words with a hash ('#'). This technique is also known as hash
tagging.</p>
      <p>
        Nine weeks after the initial announcement of the system the system's usage has
been analyzed. “Noisy” statements like as “hello” or “xxx” were removed prior to the
analysis. The remaining notes were labeled with the three types of meta-cognitive
control of Ertmer &amp; Newby [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]: evaluate, plan, and monitor. Additionally to this
model based labeling, all notes were clustered based on the contained information
using content based labeling based regarding the context factors of situated learning.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Results</title>
      <p>Over the period of nine weeks, 76 users have registered with ReScope. According to
the domains of the registered e-mail addresses, participants from 13 countries were
identified. In average, the respondents were 36 years old; the youngest participant was
22 and the oldest was 58 years old. The majority looks at the official tag cloud at
delicious.com (91%), although 73.5% of the respondents state that they look at their
tag cloud only sometimes or rarely. Nine participants left 43 notes about their tag
cloud. After cleaning the noise from the notes, 35 notes remained that describe
reflective activity of their authors.</p>
      <p>The first notes of five users reflect their surprise over the structure of their personal
tag cloud and expressed the need to adjust the tags. An example for these notes is
given by User A.</p>
      <p>“I have too many occurrences of singleton tags #clean-up”.</p>
      <p>The note of User A also shows the use of a hash tag. This feature has been used by
six participants in 14 notes. The provided hash tags were beneficial for labeling the
notes for the analysis. The following two examples illustrate the use of hash tags. In
the first note, User F stated.</p>
      <p>“need to cut out #duplicate_tags”
A more complex example of hash tags is given by the statement of User D.</p>
      <p>“Writing on my #blog (++space) I realised I hadn't used #tag podcast very
consistently. #consistency important, so I #edited the post.”</p>
      <p>All messages were labeled according the three types of reflection for
metacognitive control: evaluate, plan, and monitor. One note was labeled with evaluation
and planning because the note stated first the result of a self-evaluation and then
defined an objective for future tagging. 17 notes are labeled as evaluative reflection,
six notes as planning, and 13 notes as monitoring.</p>
      <p>The results from the model centric labeling show that all three types of reflections
were identified with the notes (see Table 2). The majority of the notes were labeled as
evaluative reflection. A fifth of all notes and two fifths of those that were tagged as
evaluative reflection referred to cleaning the tagging structure.</p>
      <p>Additionally a content based labeling has done on all annotations. After this
procedure a note could have many labels assigned. This step brought up three key
categories: 23 notes were reflections about the semantic structure of the tag cloud, six
notes were reflections on organizing the tagging process or on aligning it with other
tasks, and nine notes were reflections on system features. Furthermore, two notes
were labeled as reflections on social interaction and one note was labeled as a
personal remark. Four notes were classified as follow-ups to prior notes that marked
steps in a process. Within the notes on the semantic structure, three sub-categories
were identified. The participants reflected in seven notes on the need of cleaning up
the tag structure, in eight notes about the consistency of how the tags are used, in two
notes about emerging tags.</p>
    </sec>
    <sec id="sec-6">
      <title>Discussion</title>
      <p>
        The present study focused on the potential of tag clouds for supporting reflection on
the personal tagging of self-directed learners. It combines and extends the prior
research on visualizations of learner activity based on knowledge domain independent
information [
        <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
        ] as well as the research on using tags for identifying learner interests
in open ended environments [
        <xref ref-type="bibr" rid="ref8 ref9">8, 9</xref>
        ].
      </p>
      <p>The results show that already the rather simple visualization stimulate reflection
are conforming the models of meta-cognitive control. The notes of the content based
labeling are equally distributed across all types of reflection (Table 2). This suggests
that the tag cloud supports meta-cognitive processes in self-directed learning of all
levels similarly. Based on the present results it can be argued that tag cloud
visualizations can serve as a reflection support tool for self-directed learners.</p>
      <p>The results of the content labeling can be interpreted as instances of the context
factors for situated learning. By mapping the identified labels on the context factors, it
becomes possible to address the second research question. The design of the tag cloud
focused at the context dimensions process and concept. Therefore, it is expected that
the participants' notes are related to the context factors rhythm, value, and connection
(Table 1). Notes that were labeled only as semantic structure but not to any of the
sub-categories were mapped to the connection factor, because these notes reflect the
relations between the tags and the relations between tags and resources. Notes of the
categories process related and emerging topics were mapped to the rhythm factor.</p>
      <p>Finally, the notes of the categories clean-up and consistency were mapped to the
value factor, because these notes refer to the value of the tags for the personal
information management. Table 3 shows the results after remapping of the contextual
factors. The results show that the reflections related to the three factors were almost
equally stimulated by the tag cloud. This finding supports the expectations regarding
the relevance of the contextual factors for reflection.
8</p>
    </sec>
    <sec id="sec-7">
      <title>Conclusions</title>
      <p>Reflection is the active reasoning that has been described as the learner's assessment
and validation of experiences in problem solving and social interaction against
conceptual structures and strategies. This process is part of developing consciousness
about the relations between actions, beliefs, and concepts. Therefore, reflection is an
important meta-cognitive process related to learning. This article analyzed if a tag
cloud visualization of a learner's free form tags can stimulate such meta-cognitive
processes. This study has two important results.
1. A personal tag cloud can stimulate reflection on the tagging activity of a learner.
2. The concepts of situated learning can be applied for developing tools for
supporting self-directed learners.</p>
      <p>The findings of this study indicate that targeted solutions for supporting
metacognition do not need to be dependent on pre-structured domain knowledge. This
opens opportunities for developing new forms of supporting self-directed and
incidental learning in personal learning environments.
9
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next generation of software. Retrieved 01/12/2008 from
http://www.oreillynet.com/pub/a/oreilly/tim/news/2005/09/30/what-is-web20.html
20. Schön, D. A. (1983) The Reflective Practitioner: How Professionals think in</p>
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21. Smith, G. (2008) Tagging, people-powered metadata for the social web. Berkley,</p>
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22. Wenger, E. (1998) Communities of practice; learning, meaning, and identity.</p>
      <p>Cambridge: Cambridge University Press.
23. Wexelblat, A. &amp; Maes, P. (1999) Footprints: history-rich tools for information
foraging. Conference on Human Factors in Computing Systems. 17, 270-277.
24. Wilson, S., Liber, O., Johnson, M., Beauvoir, P., Sharples, P. &amp; Milligan, C.
(2006) Personal Learning Environments: Challenging the Dominant Design of
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