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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Integration of a Flexible Analytics Workbench with a Learning Platform for Medical Specialty Training</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Tilman Göhnert</string-name>
          <email>goehnert@collide.info</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sabrina Ziebarth</string-name>
          <email>ziebarth@collide.info</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>H. Ulrich Hoppe</string-name>
          <email>hoppe@collide.info</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Per Verheyen</string-name>
          <email>verheyen@collide.info</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Duisburg-Essen</institution>
          ,
          <addr-line>Lotharstr. 63/65, 47048 Duisburg</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>In this paper we present a generic and extensible analytics workbench and show how it can be connected to learning platforms in order to analyze the activities on the platform from different perspectives. We show that as the analytics workbench already supports a wide range of analyses like network analysis, statistical analysis, and analysis of activity logs, the main effort needed for connecting a learning platform to it lies in transporting the log data of the platform into the workbench. However the analytics workbench is also designed for extensibility so if desired more specific analysis capabilities can be added to it easily. We present an analysis of the online platform of the KOLEGEA research project for supporting medical doctors in their specialty training as a case example for how the integration can be done, for what kind of analyses can be conducted, and for how the analysis results can help both the developers and the operators of such a learning platform.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>Software tools for supporting learning often do not provide
support for learning analytics. If there is analytic support
(e.g. in larger open source projects like Moodle1 or
commercial solutions), it is mostly integrated into the specific
learning environment and cannot be easily reused for other
environments. Thus, much effort is invested in implementing
even basic analytical features again and again for different
learning environments.</p>
      <p>
        In the context of web analytics the need for simple and
economic solutions for getting (statistical) information about
the visitors’ behavior on web pages led to generic tools like
Piwik2 or Google Analytics3, which can be easily applied to
arbitrary web pages and portals. Regarding learning
analytics there are first approaches for generic analysis
environments. For example, the LeMo application provides tools
for monitoring of learning processes on arbitrary learning
management systems (LMS) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. However, for using these
tools the contents and logs of the LMS that should be
analyzed have to be transformed into the comprehensive and
very specific LeMo data base structures. There are only
few connectors, e.g. for Moodle or Clix, thus for most LMS
there would be much effort to transform the data.
Furthermore, LeMo is focussed on analysis of LMS, which are only
one aspect of learning environments. In general, the
essential challenge is the flexible integration of a generic analysis
module with different types of learning environments.
We have developed an analytics workbench4 [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], which
covers a wide spectrum of analyses and can be easily applied to a
wide range of data. This includes data from arbitrary
learning environments, since lots of standard data formats are
supported and the internal data representations are simple
and generic, thus most data can be mapped. The workbench
can be used exploratively by analysts, but it can also be used
for performing stored analysis workflows automatically and
thus for providing analysis results for other user groups [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
In this paper, we present the analytics workbench and show
how it can be easily coupled with an existing learning
platform and used for meaningful analyses regarding different
target groups. As a case example we use the integration of
the analytics workbench with the KOLEGEA occupational
learning platform for doctors in specialty training [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. THE ANALYTICS WORKBENCH</title>
      <p>Major parts of the analytics workbench as it is now have
been developed in the context of the SiSOB5 project. This
project, funded by the European Community under the
Science in Society (SIS) theme, aimed at measuring impact of
2http://piwik.org/
3http://www.google.de/intl/en/analytics/
4http://workbench.collide.info/
5http://sisob.lcc.uma.es/
science and research on society. The overall goal of the
workbench development in this project was building a generic and
extensible analysis framework with an integrated user
interface that would enable even non-computer experts to access
the full analytical power behind the tool and that would also
allow reusing and sharing the created analysis workflows.
As depicted in Figure 1 the workbench offers a web-based
user interface for designing analysis processes. The
workflows are represented in a visual language based on a
pipesand-filters metaphor, in which modules of the language
represent analysis steps and links between these modules
describe the data flow. In this representation workflows can
be stored, loaded, and also shared with other users of the
tool. This user interface is backed by a multi-agent system
and each of the modules in the visual language corresponds
to one agent in the backend.</p>
      <p>A wide range of analysis modules are currently available.
Apart from quite generic components for putting data into
the workbench, retrieving data from the workbench, or
duplicating data for splitting a workflow into parallel branches,
there are also over ten different modules connected to
processing and analyzing graphs (including several modules for
community detection and a module offering a wide range
of centrality measures), around ten modules connected to
processing and analyzing activity logs (including modules
for deriving statistical information, creating networks, and
doing sequence analysis), and a wide range of different
visualizations for both graphs and statistical information.
The evaluation studies of the analytics workbench conducted
during the SiSOB project6 showed that researchers from
different fields working in the area of scientometric research
experienced the workbench as a tool they could imagine to
use in their day-to-day work. One aspect that was
specifically highlighted were the advantages of the explicit
workflow representation in the pipes-and-filters metaphor. The
study participants saw re-usability of workflows, the
possibility to exchange workflows with other researchers, and the
possibility to communicate about the workflows based on
this representation as something that would be very
beneficial for themselves. First results of an evaluation study
conducted in the context of teaching social network analysis
using the workbench in a master level university course
confirm these findings.</p>
    </sec>
    <sec id="sec-3">
      <title>2.1 Data handling</title>
      <p>In principle the formats used for data exchange between the
individual analysis components may be chosen completely
arbitrary as long as each agent in an analysis workflow
understands the input it is given. However in order to facilitate
an easy data exchange between the individual agents, some
formats have been chosen as main exchange formats. The
format used for data tables and the format used for graph
data both stem from the SiSOB project7. Both are very
flexible JSON based formats which allow converting to and
from almost any other data format available for these kinds
of data.
6http://sisob.lcc.uma.es/repositorio/deliverables/
D63-Final.pdf
7http://sisob.lcc.uma.es/repositorio/deliverables/
SISOB-D52.pdf
Currently the workbench offers transformations between the
SiSOB Graph Format (SGF) and the edge list graph format
used by the Pajek8 network analysis tool, the adjacency
matrix format of the UCINET9 tool, and GML10, a very
widespread and expressive graph format, which can be used
for example as input and output format of the igraph11
network analysis library. The SiSOB Datatable Format (SDT)
can be converted to and constructed from comma-separated
value (CSV) files in order to allow data exchange with
almost any tool that can handle tabular data.</p>
      <p>The third main data exchange format used in the workbench
is the Activity Streams format12. It is also a JSON based
format and offers a quite flexible representation for activity
log data.</p>
    </sec>
    <sec id="sec-4">
      <title>2.2 Architecture and extensibility</title>
      <p>
        As already stated the workbench combines a web-based user
interface with a multi-agent system as analysis backend. The
system uses an SQLSpaces server [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] as communication and
data exchange platform. The SQLSpaces system is an open
source implementation of the “tuple space” [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] concept
focusing especially on ease of development using the server
as communication platform for distributed multi-agent
systems and on the support of language-heterogeneity in these
systems. Supported programming languages include Java,
Python, and JavaScript. Figure 2 shows an overview of the
architecture.
      </p>
      <p>While agents offering analysis techniques are the majority
in the system, agents also control input and output of data
to and from the analysis process. Therefore connecting the
system to new data sources, feeding output of workflows
to other systems, and adding new analysis techniques can
8http://pajek.imfm.si/doku.php?id=pajek
9https://sites.google.com/site/ucinetsoftware/
10http://www.fim.uni-passau.de/fileadmin/
files/lehrstuhl/brandenburg/projekte/gml/
gml-technical-report.pdf
11http://igraph.sourceforge.net/
12http://activitystrea.ms/
be realized by adding new agents to the analytics
workbench. Apart from the technical basis, the connection to the
SQLSpaces, a newly developed agent only needs to comply
with the tuple protocols used in the system. There is no
further restriction regarding the structure or the functionality
of the agents.</p>
      <p>
        Another possible entry point for adding new functionality
to the analytics workbench is the R-Analysis agent, which
acts as a wrapper for scripts to be executed in R13, a
language for statistical computing. As there is a wide range of
R libraries for different analysis purposes including network
analysis available, this allowed and still allows easy
integration of analysis features based on these libraries. One
example for the integration of experimental or newly
developed analysis techniques based on R is the integration of a
novel approach for multi-relational blockmodeling [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
      </p>
    </sec>
    <sec id="sec-5">
      <title>3. THE KOLEGEA LEARNING PLATFORM</title>
      <p>
        The project KOLEGEA14, which is facilitated by the
German Federal Ministry of Education and Research, aims to
support doctors specializing in family medicine (general
practice (GP)) by providing a platform for collaborative
learning in occupational, social communities. It thus addresses
the problem of missing opportunities for networking, which
highly restricts occupational knowledge exchange as well
as collaborative learning in peer communities among young
doctors. This problem results amongst others from the many
job changes which are required by the broad curriculum of
family medicine. Since GP specialty training is based on
learning by solving real problems/cases in every day
working life, learning is problem-based, self-directed and based
on intrinsic motivation. Thus, KOLEGEA’s pedagogical
approach (see also [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]) is focused on collaboratively
working with user-generated cases in the spirit of problem-based
13http://www.r-project.org/
14http://www.kolegea.de/
learning (PBL) (see e.g. [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]). Users can share and discuss
cases in self-regulated or mentor-supported small groups and
share the results with the community. Cases can be enriched
with media like pictures or videos, tags and links to medical
guidelines or external online information like recent
publications. Apart from the work in small groups, there are tools
for community support like forums, which can be used for
occupational, but also social exchange.
      </p>
      <p>The current version of the KOLEGEA system consists of a
web portal15 and mobile applications (tablet16 and smart
pen) for multimedia note taking and editing. Smart phone
apps for (simple) note taking and accessing the system are
currently in development.</p>
      <p>
        The portal provides access to the virtual community and its
knowledge artifacts (user-generated content as well as
medical guidelines and links to artifacts of current research).
Figure 3 shows an example of a case description, its discussion
and metadata (e.g. tags). The case description is structured
based on the phases of the medical consultation. Following
Steinkuehler et al. [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], we consider group discussions to be
asynchronous and threaded, since this can produce
discussions and results of higher quality than synchronous
communication and is more flexible regarding time. Discussions
can take place directly connected to cases, but also in the
community’s forums.
“An important issue in groupware and CSCW is awareness
– generally having some feeling for what other people are
doing or having been doing” [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], since “the success of a
collaborative learning experience depends on the informed
involvement of curriculum designer, teacher, evaluator, and
students” [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. Each of these roles needs different
awareness information. In KOLEGEA target groups for
aware15https://beta.kolegea.org/kolegea/
16https://play.google.com/store/apps/details?id=
info.collide.kolegea.npad.views&amp;hl=en
ness information are the researchers designing and
evaluating the platform, the platform operators, the mentors and
of course the trainees. Researchers and platform operators
are interested in the success of the designed tools, processes
and stimuli to further improve the system. Furthermore,
platform operators need input for operating the platform
like which case to select as ”case of the month” or which
trainees have the potential for supporting (or ”tutoring”)
self-regulated groups or even become mentors after
becoming medical specialists. Mentors e.g. need information on
how the members of their groups work together to support
collaboration. Trainees might be interested in the activity
of groups and their topics before asking for membership.
These are just a few examples for awareness needs in the
KOLEGEA project.
      </p>
    </sec>
    <sec id="sec-6">
      <title>4. INTEGRATION DESIGN</title>
      <p>The analytics workbench provides many standard analysis
modules for SNA and statistical analysis of log files.
Furthermore, it can be easily extended for specific analyses needed
for the actors of the KOLEGEA system. Since it is more
efficient to reuse existing software (modules) instead of
developing it from scratch (e.g. reduced implementation time,
less bugs due to prior testing and usage) the analytics
workbench was coupled with the KOLEGEA system for
performing the needed data analysis.</p>
      <p>In KOLEGEA all textual contents as well as the logging
information are stored in a PostgreSQL data base, media
files like images or videos are stored in the file system of the
web server. While the data is directly accessed by the web
platform, the mobile applications use a web service interface
(REST) to write and access data. The mobile devices also
send their log files to the central data base using the web
service interface. The KOLEGEA logging format is
proprietary.</p>
      <p>To integrate the analytics workbench with the KOLEGEA
system the KOLEGEA WebServices were extended to
provide raw data for the analysis (log files as well as
information on objects and users stored in the data base). This data
is preprocessed by a specialized module which converts the
KOLEGEA log file format into the Activity Streams format
that is supported by the workbench. Furthermore, there
is a specialized module for creating actor-artifact networks.
After this preprocessing, mainly generic modules for log
analysis and social network analysis provided by the workbench
are used for analyzing the data.</p>
      <p>At the moment the analysis results are manually compiled
into reports for the project members. We plan to extend the
KOLEGEA WebServices to receive analysis results that are
stored in the internal data base and provided by the
platform. The complete analysis process (see Figure 4) will then
contain the following steps: Analysts define analysis
workflows in the workbench and save them in the tuple space. A
scheduling agent takes the workflow definition and initiates
its execution by writing the appropriate command tuples
in defined intervals. In each workflow run specific input
agents access the KOLEGEA WebServices to retrieve the
data needed for the analysis. The specified analysis agents
prepare and analyze this data and visualization agents
create appropriate visual representations of the results (e.g.
sociograms). The textual and visual results are transferred to
the platform by an output agent, which accesses the
KOLEGEA WebServices. These save the results in the platform’s
database to be retrieved and visualized on demand.</p>
    </sec>
    <sec id="sec-7">
      <title>5. DATA ANALYSIS</title>
      <p>The following sections describe exemplary analyses on
different levels conducted with the analysis workbench to support
different types of actors regarding the KOLEGEA system.</p>
    </sec>
    <sec id="sec-8">
      <title>5.1 Effects of stimuli</title>
      <p>Log statistics over time can be used to identify effects of
stimuli. Figure 5 shows the number of distinct users per
day in the “closed beta” phase of the project. Since the
platform was only used by a closed group of users, there was
no registration via the platform, but the login information
was send via mail to the preselected test users. On this day,
there was the highest amount of distinct users. After a week
an activation mail was send to the trainees informing about
new cases. This resulted in a higher number of distinct users.
Direct contacts with the test users on the DEGAM day of
family medicine as well as the later activation mail do not
seem to have had much effect.
This indicator was similarly used to evaluate the effects of
events advertising KOLEGEA regarding registration
numbers in the “open beta” phase in January 2014.
Furthermore, we used login statistics for identifiying a good weekly
date for sending activation emails with information on recent
platform events.</p>
    </sec>
    <sec id="sec-9">
      <title>5.2 Recommendations for “case of the month”</title>
      <p>In KOLEGEA each month one case is selected as “case of
the month” and depicted on the top of the welcome page.
While the case is ultimately selected by a group of doctors
of the institute for family medicine of the Charit´e Berlin to
guarantee the quality of its content, not all available cases
should be considered to reduce their effort.
Indicators for interesting cases are a high number of
comments and read events as well as distinct users and distinct
returning users accessing the case. While most of this
information could have been gained by using the existing generic
components for log statistics, to have all information in one
table a specific “KOLEGEA Case of the Month” component
was implemented. This component is applied after loading
the logfile and filtering (excluding) actors of the role
“admin” by existing components. The results (see Figure 6) are
displayed by the table viewer, which allows sorting of the
table rows by selecting a column caption.</p>
      <p>The statistics were provided to the doctors as a basis for
selecting the “case of the month” at the end of January 2014 for
the first time. They chose a case with many comments and
medium accesses, which was created by a doctor in training.</p>
    </sec>
    <sec id="sec-10">
      <title>5.3 Identification of user roles</title>
      <p>While the previous examples are mainly based on
descriptive statistics generated from logfiles, in this analysis the log
information is aggregated into a network for network
analysis.</p>
      <p>Figure 7 shows a three-mode network of the complete
KOLEGEA community containing actors (green dots), cases
(blue squares) and forum threads (orange triangles). There
are three different types of edges: green edges indicate that
an actor only read an artifact, orange edges show that the
actor at least added one comment or tag to a case/forum
thread and blue edges identify the creators of the artifacts.
Thus, comments and tags are already aggregated in the
edges.</p>
      <p>Most actors only interact with artifacts by reading them,
which is typical for online communities. The community has
a core of actors being connected with many artifacts and a
periphery of actors being only connected to few artifacts.
The core contains two mentors, a KOLEGEA team member
and ten users. Users with a high degree centrality regarding
reading edges and no or little writing edges seem to be very
interested in the artifacts and might need just a little nudge
to participate actively.</p>
      <p>Regarding the identification of potential tutors and
mentors highly active users are interesting. Considering only
create (case/forum tread/comment) edges, the degree
centrality respectively strength (weighted degree centrality) is
an indicator for the level of activity in the platform. The
the degree centrality of the cases in the multi-mode network
corresponds to the number of distinct users in the “case of
the month” statistics in section 5.2 .</p>
      <p>Figure 8 shows an one-mode actor network, which is
created by “folding” the actor-artifact network ignoring
“read”edges. From the point of view of data aggregation this
folding operation transforms the previous multi-mode network.
The nodes are sized regarding their betweenness centrality.
A high betweenness centrality is an indicator that the
respective actors have a mediator role in the community, thus
these might especially qualify for becoming tutors or
mentors. The four most central actors are three mentors and one
user. This supports that betweenness centrality is a good
indicator for identifying mentors/tutors. The high centrality
of the mentors is a consequence of building a new
community (”cold start problem”). Furthermore, user325 appears
to be a good candidate for becoming a tutor.</p>
    </sec>
    <sec id="sec-11">
      <title>6. SUMMARY AND PROSPECTS</title>
      <p>In this paper, we have shown how a generic and
extensible analytics workbench can be integrated with an online
learning platform for medical doctors in specialty training
for performing analyses. We also have presented how the
results of different analysis processes with different
perspectives on the available data can be used to inform researchers
developing online learning platforms and operators of such
platforms. The analyses addressed miscellaneous levels of
data aggregation ranging from basic log data to one-mode
networks. There are relations between the analyses, e.g. the
number of distinct users linked to a case can be extracted
directly from the log file or as the degree centrality from
a case-actor network. An actor-artifact network, which is
based on a logfile, can be aggregated into an actor-actor
network for getting a more condensed view on user
interactions.</p>
      <p>In our future work, we plan to extend the work presented
here in several ways. One direction will be the extension
of the workbench with further analysis modules focused on
the analysis of activity logs. Another direction will be the
application of more of the already implemented analysis
approaches on the log data of online platforms, e.g. the
available sequence analysis modules. We also plan to build a
collection of reusable analysis workflows that can be applied
to different online platforms and that can support different
target groups. In addition to researchers developing new
approaches for learning platforms and operators of such
platforms, we also plan to support the users of the platforms
directly with awareness features. A last goal for both the
development of the analytics workbench and the KOLEGEA
platform will be integrating the two in such a way that it is
possible to directly view the results of the workflows in the
platform and thus giving especially the users of the platform
an easy access to the analysis results.</p>
    </sec>
  </body>
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