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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Representing Computer-Supported Collaborative Learning macro-scripts using IMS Learning Design</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Davinia Hernández-Leo</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Daniel Burgos</string-name>
          <email>daniel.burgos@ou.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Colin Tattersall</string-name>
          <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>Educational Technology Expertise Centre, Open University of the Netherlands</institution>
          ,
          <addr-line>PO Box 2960, NL-6401DL, Heerlen</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Telecommunications Engineering, University of Valladolid Campus Miguel Delibes</institution>
          ,
          <addr-line>47011 Valladolid</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>IMS Learning Design (LD) is a specification that aims at computationally representing any learning process. However, the possibilities of LD to represent collaborative learning scenarios are being questioned by the Computer-Supported Collaborative Learning (CSCL) community. In this paper we analyze the LD support to realize CSCL macro-scripts, which describe flows of coarse-grained activities. We first identify the requirements of the scripts for their representation using LD and, then, study the possibilities of LD to support each of these needs by means of two significant scripts that representatively feature the requirements. The paper indicates the conclusions from this analysis showing the capacity of LD notation to express CSCL macroscripts but also considering the support of related specifications and tools.</p>
      </abstract>
      <kwd-group>
        <kwd>IMS Learning Design</kwd>
        <kwd>Computer-Supported Learning</kwd>
        <kwd>Collaboration Scripts</kwd>
        <kwd>Learning Management Systems</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>
        Computer software for supporting scripted Collaborative Learning (CL) is designed
with the aim of scaffolding social interactions among participants [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. CSCL
macroscripts structure CL scenarios by defining the composition of groups, the distribution
of roles and resources as well as the coordination of the activities that make up the
learning process [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Up to now, these scripts are “hardwired” in specific
CSCL applications. This approach has clearly many drawbacks mainly related to time
and cost efforts in development. To overcome these problems, a promising approach
is to formalize the scripts so that they are automatically interpreted by an engine
integrated in a learning management system (LMS). This paper focuses on the
computational representation of CSCL macro-scripts (hereafter “scripts”).
      </p>
      <p>
        In order to computationally represent the scripts we propose the use of IMS
Learning Design specification (LD). LD is broadly accepted as de facto standard to
formally model interoperable Units of Learning (UoL). The specification was
designed so that UoLs can describe any teaching-learning process [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. However, the
LD support for implementing CSCL scripts is not clear. Since LD is a recent
specification (2003), there are not significant examples and efforts that show the
possibilities of LD for CSCL. Besides, there is a lack of clarity regarding which
characteristic of the scripts should be expressed by the notation itself as opposed to
which requirements can be supported by tools or even other related specifications.
Although partial work has been already accomplished [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], a more complete and
systematic analysis is needed. As a consequence, some researchers are proposing
alternative languages to describe CL scenarios [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>
        In this paper we systematically analyze the support of LD to implement the main
requirements of CSCL macro-scripts. Therefore, Section 2 identifies the educational
design requirements of scripts and illustrates them by means of a significant script:
Universanté [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Two scripts that extensively feature the requirements are used to
analyze the implementation of the requirements with LD. The section collects the
results of this analysis concerning Universanté script. Finally, Section 3 concludes the
paper by confronting the differences between the requirements that can be satisfied by
the LD notation and the needs that can be solved using tools or related specifications.
2
      </p>
      <p>
        Expressing CSCL macro-scripts requirements with IMS LD
This section presents the educational design requirements of CSCL scripts, which
we have identified in the CSCL literature: mostly current research on framing the
components and mechanisms of scripts [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] and other complementary sources such as
[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Table 1 describes the requirements which include common
collaborative learning mechanisms related to group composition, role/resource
distribution and coordination. Significantly, all the requirements are representatively
featured in two of them: Universanté and ArgueGraph [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Universanté,
which exploits socio-economics and cultural differences for teaching community
health to students of different countries [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], is used in Table 1 to illustrate the
requirements.
      </p>
      <p>
        Altogether, the main drawback of scripts is their associated “risky” flexibility
restrictions [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Inflexible extrinsic constraints, such as the duration of activities, can
spoil a satisfactory enactment of the learning scenario [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. It requires modifications on
the fly regarding the time structure, the resources or even the activities themselves
and their order. These flexibility requirements are being deeply analyzed concerning
adaptive situations for individual learning [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Nonetheless, a common
flexibility-demanding characteristic that significantly appears in CSCL scripts refers
to flexible group composition. A typical problem of CL is the variability of students’
participation. It is often impossible to guess the precise amount of participants that are
attending a particular session, if they will be an even or odd number, whether some of
them will join the class afterwards or cannot participate in a specific moment [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
These situations require unexpected group composition modifications.
      </p>
      <p>Table 2 presents the lessons learned when expressing the requirements of the
Universanté script with LD. The table also includes selected excerpts of suggested
coding (the complete LD package, also of ArgueGraph, their use case narratives and
activity diagrams are available on-line at http://gsic.tel.uva.es/collage/scripts).</p>
      <sec id="sec-1-1">
        <title>Description</title>
        <p>CSCL scripts typically make use of groups forming
hierarchies, i.e., groups may be composed of other
(smaller) groups or different (individual) roles
Defining the desired number of group members is
perhaps the most common suggestion of scripts
regarding group composition. They usually
recommend keeping group size small for short
activities because, for example, there is not enough
time for the group to become effective. However,
larger groups are adequate in long scenarios
Many scripts require a certain number of groups or
at least a minimum or maximum amount so that the
dynamics they propose are afforded
Depending on the scenario groups should be
heterogeneous or homogenous to be more effective.
The groups can be formed either by the students
themselves or by the teacher by referring to existing
common features (e.g. gender, age) or simply using
a random assignment policy
Some CSCL scripts need some groups to be formed
at runtime. That is, group assignment may depend
on the result of a previous activity
In a CSCL script participants may assume one or
more roles at the same time (e.g. one of the students
in a group is assigned to the role “scribe”). In
addition, participants can switch their roles with
other participants (e.g. rotation of roles)
The amount of resources and their distribution may
depend on the number of groups, roles and
participants
The main problem of the activity coordination falls
into the synchronization of groups and roles
through the activities: a person may belong to a
group in a certain activity and to another group in
the following one (then she probably needs to wait
for the rest of the members of her second group in
order to start the second activity)
While working together in the same activity,
learners’ actions are sometimes guided or
constrained according to floor control mechanisms
(e.g. a model of turn-taking when modifying an
artifact)
Artifacts (e.g. a document) are often created by an
individual or a group. They may be used in
different activities and by different individuals or
groups of the same script</p>
      </sec>
      <sec id="sec-1-2">
        <title>Illustration: Universanté script</title>
        <p>There are country groups and thematic groups.
Each thematic group is composed of case
groups
(See amount of groups and group formation
policies. Since there are at least two countries,
each case-group has (at least) 2 persons of
different countries. Since there are 2 cases per
theme, each thematic-group has (at least) 4
persons. Since there are four cases, each
country-group has (at least) 4 persons)
At least two different thematic groups, two case
groups (per thematic) and two country groups
Each case group is formed of at least 1
participant per country
(Not applicable)
Each person belongs to three different types of
groups, which implies playing specific roles
depending on their “case”, “theme” and
“country”
All case descriptions are distributed evenly
among all case groups
- Within each case group, all participants
discuss a clinical case using a discussion forum;
regularly the case groups with the same
thematic gather in the same discussion forum
and identify common points and differences
between the cases; […]
- Within each country group, the members of
each thematic group in turn present (face to
face) a synthesis of their case experience;
- Within each thematic group, the members of
each country group create a fact sheet
concerning the thematic status in their country;
[…]
- Within each country group, the members of
each thematic group in turn present their fact
sheets; […]
- Within each country group, the member of
each thematic group modify the fact sheet
according to the methodological comments;
[…]
Fact sheets and health strategies are shared
artefacts that require floor control mechanism to
ensure data consistency.</p>
        <p>Since the fact sheets are created until they are
finally made available to the teacher, they are
used in discussions within theme groups,
presented within country groups, commented by
the teacher, and modified by their authors.</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>Conclusions</title>
      <p>
        CSCL macro-scripts aim at structuring collaborative learning processes of
coarsegrained activities. Their requirements are shaped around the fact that they involve
groups and multi-roles characteristics. The many possibilities of LD to support the
identified needs have been tested by means of two scripts (Universanté and
ArgueGraph Scripts) that significantly feature the requirements. Returning to the
different types of requirements, we summarize now how they are addressed by the
notation itself and/or by other specifications and tools:
− The LD roles component and its related elements and attributes together with the
joint use of properties and conditions provide constructs to computationally
represent several group composition requirements (mainly hierarchy of groups,
group size and dynamic group formation). The notation provides limited support
for the formal specification of the number of groups and group formation policies.
However, these requirements as well as an enhanced realization of the others can
be supported by related administration tools (and also supporting tools such as
grouping services) in combination with eventual group composition specifications.
− Similarly, role distribution relies on the constructs offered by the roles component,
in this case complemented with the coordination of role-parts, in each of which a
participant may play different roles. In addition, supporting tools may define
specific roles implying different privileges when using the tools. Rotation of roles
can be realized by rotating activities or by using mechanisms eventually provided
by the players. The distribution of resources is facilitated by the coordination of
role-parts but also through the possibility of referencing resources to different
elements of LD such as activity-descriptions or environments. The use of properties
or supporting tools also provides another means of resource distribution.
− Coordinating the flow of CL activities is feasible using the LD method and
conditions. The flow of artifacts between activities can be attained by employing
properties, global-elements and monitor services (as well as other specialized
supporting tools) conveniently referenced by other LD elements. The consistency
of shared artifacts is ensured by jointly held properties. Moreover, sophisticated
floor control mechanisms can be realized by using supporting tools.
− Flexibility requirements are also tackled by both the LD notation and its
implementation in tools. The main attributes of roles that enable flexible group
compositions are min-persons, max-persons and create-new. Further flexibility is
provided by the capabilities of LD to support adaptation and the distinction
between abstract descriptions (UoLs) and specific instantiations (runs). This
distinction affords new developments allowing modifications to runs in progress.
Concluding, computationally representing CSCL macro-scripts using the LD
interoperable notation provides the following benefits. Firstly, they can be repetitively
and automatically processed. In addition, they can be reused in different settings and
with different participants. And, furthermore, they can be easily adjusted to support
other learning scenarios by using LD-compliant authoring tools. Current development
in this area aims at teacher-friendliness and is focused on visual representations and
the reuse of learning design solutions [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. These editors should hide the computer
representational details laid out in this article.
Davinia Hernández-Leo acknowledges partial financial support to the Spanish
Ministry of Education and Science project TSI2005-08225-C07-04, Autonomous
Government of Castilla and León project VA009A05, Kaleidoscope NoE
FP6-2002IST-507838 and, especially, the Research Fellowship Program of the University of
Valladolid. This program facilitated a visiting Research Fellow at the Educational
Technology Expertise Centre (OTEC) of the Open University of the Netherlands. The
authors would like to thank the rest of the members of the OTEC centre and of the
GSIC/EMIC group at the University of Valladolid.
      </p>
    </sec>
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