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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Learning Analytics Implementation in a Multidomain Computer-Based Learning Environment</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Omar Álvarez-Xochihua</string-name>
          <email>aomar@uabc.edu.mx</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pedro J. Muñoz-Merino</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ricardo García-Pericuesta</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>José Á. González-Fraga</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Carlos Delgado Kloos</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Everardo Gutiérrez-López</string-name>
          <email>everardo.gutierre@uabc.edu.mx</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>María Andrade-Aréchiga</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Telematics Engineering, Universidad Carlos III de Madrid, Av. Universidad</institution>
          ,
          <addr-line>30, E-28911 Leganés, Madrid</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Telematics, University of Colima, Av. Universidad</institution>
          ,
          <addr-line>333, Las Víboras, 28040 Colima, Colima</addr-line>
          ,
          <country country="MX">México</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Science Faculty, Universidad Autónoma de Baja California</institution>
          ,
          <addr-line>Carr. Ensenada-Tijuana 3917, Ensenada, B. C.</addr-line>
          ,
          <country country="MX">México</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper presents the design and implementation of a Multidomain Learning Environment that integrates and interconnects different heterogeneous educational applications. The learning environment has three main aims: 1) to interconnect web-based educational applications regardless of their development programming language, operating system and physical location; 2) to allow students access to the set of educational applications by using a unique and secure user account; and 3) to share the students' data generated by each application, in order to be used as an integrated learning analytic approach. The implemented system is both robust and scalable; based on federated identity architecture enables institutional nodes to share single educational applications, allowing their users to obtain access to the whole applications network using the same identification data. We extended the conventional implementation of identity federation by allowing the capture, integration and analysis of students learning traces from different sources.</p>
      </abstract>
      <kwd-group>
        <kwd>Learning analytics</kwd>
        <kwd>Federated learning environment</kwd>
        <kwd>Multidomain learning analytics</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Computer-based educational systems are intended to support the further development
of the learning process and address the need to personalize instruction in a massive
way. Educational software is supporting a diversity of domains at all the educational
levels. However, there is still a lack of effective integration or communication among
those systems, triggering three main problems: 1) single users with multiple systems
accounts; 2) redundancy and inconsistency of users’ information; and 3) minimal or
Copyright © 2017 for the individual papers by the papers' authors. Copying permitted for private and academic purposes. This volume is published and copyrighted by its editors.
null use of data generated by the same user while using different applications (e.g.
access time preference, hints inclination, typing speed, cognitive level, and so forth).</p>
      <p>
        Nowadays, there exist some ways to avoid the use of multiple user accounts, by
implementing authentication protocols such as Open standard for Authorization
(OAuth) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], Single sign-on (SSO) [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] and the Security Assertion Markup Language
(SAML) [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]; standards intended to utilize a unique user account to gain access to
multiple independent software systems. However, the use of these access control
mechanisms are mainly focused on authentication, authorization and security issues
[
        <xref ref-type="bibr" rid="ref4 ref5">4, 5</xref>
        ], wasting the potential benefit to share relevant users' information and implement
an interoperable learning analytics (LA) approach that integrates data from different
platforms or systems [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
      <p>There are a number of web-based educational systems and learning platforms (e.g.</p>
      <p>
        Moodle, Open edX, Blackboar, etc.) available for students and teachers. Through
these applications, a wide variety of learning activities are conducted by students, and
educators can analyze students learning performance and behavior [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Nevertheless,
although some of these educational systems allow the use of the user authentication
standards mentioned above, most of the time, different instances of these applications
are not interrelated [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Not taking advantage of the opportunity to share important
educational data of students, in order to conduct a more comprehensive multidomain
learning analytics activity.
      </p>
      <p>This paper presents the design and implementation of a Multidomain Learning
Environment (MDLE). First, we describe related work and the use of the SAML
authentication standard, as a useful and effective tool to integrate and interconnect
heterogeneous educational software systems. Then, we show the learning analytics conducted
by different application within MDLE. Finally, we discuss how the analysis of data
about learners can be enhanced by implementing a multidomain learning analytic
approach.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>Efforts to simplify the use of multiple computer-based systems are intended to reduce
the overwhelming task to manipulate different user accounts and passwords. At the
same time, users, in their own benefit, may require the integration of data generated
from multiples applications; over the complete set of communication, entertainment
or educational systems they use.</p>
      <p>
        Nowadays, the variety of web applications and social networking tools has
fomented the use of authentication protocols, such as SSO, SAML and OAuth [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Single
sign-on is a method that enables users to gain access to multiple enterprise software
systems using a unique login account [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Commonly, the enterprise software
applications are independent but related, and important data could be exchanged on behalf of
organizations or the systems’ users. Furthermore, a SSO extension, using a protocol
like SAML, allows the interaction between enterprises by using federated
authentication; described as a mean to interchange the user's identity across organizations [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
By using a Federated Identity Management system, beyond sharing authentication
privileges, additional information can be interchanged between the network nodes,
such as users’ performance, preferences or dislikes. Recently, the use of the OAuth
authentication standard has become popular on social networking applications such as
Google, Facebook, GitHub and others [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. This protocol allows users to authorize a
website to access their information available in other applications; using the original
authentication data. Social networking sites and other web-based applications
commonly use this technology to facilitate the users’ authentication process and
information sharing. However, the objective of the implementations and research
conducted in this area is mainly focused on providing a secure interconnected environment
and guarantee users’ privacy [
        <xref ref-type="bibr" rid="ref3 ref5 ref9">3, 5, 9</xref>
        ].
      </p>
      <p>
        Even though it is possible to share users’ data between interconnected applications,
there is not enough research work describing the use of this capability to implement
learning analytics functionalities. Dyckhoff and colleagues [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] present the design and
implementation of eLAT, an exploratory Learning Analytics Toolkit that uses data
from different systems to conduct a more comprehensive teaching and learning
analysis. The authors of this paper stressed the importance of interoperability in learning
analytics, highlighting that a LA tool that “…can collect and analyze data from
different platforms is required” [6, pp. 62] and that “Current Learning Analytics tools
should be interoperable with different learning environments and systems” [6, pp.
71]. The proposed toolkit was tested with data from three different learning
environments. However, they are not considering the possibility of the same user using more
than one system, and how this data from different sources can improve the analytics
process.
      </p>
      <p>A similar work is presented by Brusilovsky [10]. In it, the author describes the
implementation of KnowledgeTree, an adaptive e-Learning architecture that integrates
distributed servers hosting educational services. This educational environment, by
using a SSO approach, allows users to authenticate through a unique service named
learning portal. Similar to our work, KnowledgeTree includes three additional
servers: activity servers, which include reusable educational content and services; student
model server, representing the current competencies and needs of students in order to
adapt instructional materials available in several courses; and finally, the
valueadding service, used to add a higher level adaptive functionality, such as content
integration and sequencing. The author considers that multiple instances of
KnowledgeTree can collaborate and interchange students’ data with each other, however, there
is no specific functionality intended to conduct learning analytics.</p>
      <p>In 2010, Arnold [11] conducted an analysis emphasizing how academic analytics,
at institutional level, have the potential to improve students’ performance. By
institutional scope they refer to data from different educational systems. More recently, the
Report on Building the Field of Learning Analytics for Personalized Learning at
Scale, published in 2014 by The Learning Analytics Workgroup, in its section on
priorities for research, describes three grand challenges as main focus areas for early
research in LA. The third grand challenge refers to creating multimodal learning
analytics by “Expanding education to capture contextual features of learning
environments…” [12, pp. 45]. Particularly, this challenge emphasizes the importance of
developing SSO infrastructure to integrate data from heterogeneous platforms with
multimodal data sources. In 2016, the LAK community organized the Cross-LAK
workshop, aimed at encouraging participants to explore blended learning by researching
and implementing LA across physical and digital spaces. Being the first theme
addressed: learning analytics across digital spaces, where the main objective was to
discuss about applications of learning analytics using multiple educational learning
environments to facilitate learning activities [13].</p>
      <p>In this work we describe the implementation of an educational environment using
the enterprise federation protocol supported by SAML. Emphasizing, the importance
of users’ behavior and performance data sharing, such as self-esteem, learning
preferences, study habits and cognitive level, in order to provide a more comprehensive
learning analytics functionality.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Learning environment description</title>
      <p>This section details the design and implementation of the MLE system, as well as
educational services currently available in the environment. We start describing the
architecture that supports the integration and communication within the proposed
environment. Then, we present the mechanics of the interaction process and the
learning analytics features of two educational applications integrated within the
environment.
3.1</p>
      <sec id="sec-3-1">
        <title>Federated Identity Architecture</title>
        <p>We implemented and configured a Federated Identity (FI) architecture that allows
secure access to the integrated MDLE system, and serves as a repository of
educational computer-based applications. The implemented architecture is both robust and
scalable environment that allows the integration of heterogeneous applications in
relation to its development environment and format of educational material. Based on
a Full Mesh Federation (FMF) principle, applications could be hosted by an academic
institution and users from other institution can benefit from such applications by
establishing a circle of trust.</p>
        <p>Full mesh federation is one of the most common and frequently used federation
architecture. Also, the FMF principle is the simpler to implement, since federation
activity is distributed and there is no need for a central hub or component that requires
to be specifically protected by administrators. Instead, in this category of federation,
the responsibility of users’ administration is distributed across the different nodes. In
this work, in order to obtain an independent and scalable environment, the FMF
architecture was chosen to implement our federated architecture.</p>
        <p>In Figure 1, we can observe the implemented architecture for the MDLE system.
Three academic institutions (UABC, UCol and IPN), current nodes participating in
this federated network, exemplify the interconnectivity of the environment. Two of
these nodes (UABC and UCol) were configured with their own identity Provider
(idP), connected to a local database storing information about its own users, and an
arbitrary number of Service Providers (SP) were installed. The idP is in charge of the
access control to the MDLE and the SP manage specific educational applications. The
role of the IPN node is only as consumer of the available federated services.</p>
        <p>All these entities (idP and SP), are typically listed in a SAML metadata file, which
is consumed by all of them. The metadata file basically describes all the shared
services and information available in the environment. In the federation, each institution
decides which services would be shared within the circle of trust, and also determines
which attributes of the users are going to be available, such as name, age, email,
among others. Using the circle of trust, configured among the environment nodes,
information about the academic performance of students could be shared between the
educational applications. Specifically, we have a database containing information
about the educational background of users. This information is obtained, firstly, from
the Preliminary Evaluation system, based on a set of diagnostic instruments (hosted
in the UCol service provider); as is explained later. Then, this information, optionally,
can be used or complemented by any other system on the network. Our aim is to use
this shared database to conduct more comprehensive learning analytics functionality
and personalize instructional content.</p>
        <p>Regarding the entire MDLE functionality, there are three different user profiles:
administrator, teachers and students. Administrator can manage (accept, activate and
deactivate) user accounts. Teachers manage the content and learning activities and
each of them is able to view his/her students’ progress. Finally, students are able to
attend their learning activities and view their generated learning analytics information.
Figure 2a shows the registration or login webpage, where users can choose which
identity provider they want to use, based on their educational institution. In Figure 2b
we can see six different services available within the MDLE environment, including
the Preliminary Evaluation (Diagnostic) and the PreMath systems described below.
First experience with the MDLE system takes place using the Preliminary Evaluation
system. This module is intended to identify educational gaps of freshman students in
the fields of mathematics and reading and comprehension, as well as evaluates aspects
regarding study habits and self-esteem; which are themes considered significant on
the success of the education of university students [14].</p>
        <p>This system, through the use of specific assessments, consisting of multiple choice
questions, evaluates students’ knowledge and academic behavior (see Figure 3).
Students are asked to answer all of the assessments in order to gain access to the rest of
the educational services available in the MDLE environment. The information
obtained is processed and used as a starting point for the assignment of activities to each
student; based on his/her specific knowledge gaps and learning habits. Detailed
analysis can be conducted locally on the data generated. In addition, this data can be used
to complement learning analytics of other educational systems in the MDLE.
Regarding the technical characteristics of the system, this computer application was
implemented using the .NET Framework developed by Microsoft. Particularly, the system
was built using the Visual C# language and the SQL Server database management
system for the data layer.
3.3</p>
      </sec>
      <sec id="sec-3-2">
        <title>Pre-university Mathematics System</title>
        <p>Another computer-based educational application, integrated within the MDLE
environment, is an Intelligent Tutoring System (ITS) supporting high-school and
university students to enhance the understanding of mathematics. This system is intended to
help freshman students to address gaps in their math current knowledge. The
Preuniversity Mathematics system (PreMath system), embedded in a Moodle
environment, includes a set of instructional content (instruction and practice), considering a
set of 20 math topics such as: multiply and divide monomials, monomial with an
integer exponent, fractions, decimals, percentages and other topics learned in previous
educational levels (see Figure 4). The PreMath system aims to reduce the university
failing grades and drop-outs rates. The set of topics included in PreMath was defined
by a group of university math professors, which were invited to make specific inputs
about the most complicated math topics causing difficulties for students to succeed in
their freshman year courses [15].</p>
        <p>When the students interact with the system, they are provided with theoretical
content (see Figure 5a), and then requested to solve a minimum of three math exercises
for each topic. Each topic consists of 50 exercises with different level of complexity.
The system provides feedback in a proactive (when a student commits a mistake) and
reactive (under student request) way (see Figure 5b). The inputs of students and
feedback provided by the system are used to conduct learning analytics; providing
information on the performance of students and quality of the educational content. Details
about the PreMath learning analytics features are described in the next section.</p>
        <p>As an example of the heterogeneity supported by the implemented MDLE
environment, different to the Preliminary Evaluation system, the intelligent tutor core of
PreMath was made using the PHP language, XML and MySQL. In addition, the
instructional content was built using the Adobe Flash platform.
4
4.1</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Implemented Learning Analytics Techniques</title>
      <sec id="sec-4-1">
        <title>Preliminary Evaluation Module</title>
        <p>Considering the four key elements included in the learning analytics definition:
measurement, collection, analysis and reporting of data about learners [16], the
preliminary evaluation module mainly works as an early alert system for the whole MDLE
environment. First, by using the domain specific assessments (see Figure 6a) the
system evaluates, collects and stores the students’ data. Second, the system measures
students’ background knowledge and learning behavior. This information is stored in
the MDLE shared database, and is available to be used for any other application on
the network. Then, a deep analysis is conducted to determine those students that
require leveling courses, and in what particular domains. Based on this information, the
MDLE core runs a process by which the students are referred to use the rest of the
available educational modules in the environment (math, reading and comprehension,
study habits and self-esteem). Finally, this module generates and displays information
about students’ performance, as described next.</p>
        <p>In order to provide adequate visual analytics for students and teachers, it was
considered the four user-interface design criteria used in [17]:
 Adding a simple interface for the learning analytics visualization charts.


</p>
        <sec id="sec-4-1-1">
          <title>Using meaningful color code.</title>
        </sec>
        <sec id="sec-4-1-2">
          <title>Organizing the visualizations into significant sections.</title>
        </sec>
        <sec id="sec-4-1-3">
          <title>Designing the whole visualization using a consistent approach.</title>
          <p>The student view is intended to provide a graphical representation of their current
knowledge (for all the considered domains), that motivate and enable them to make
flexible and adequate decisions about what material they want to review. The level of
academic performance of students is displayed by using color-code. As shown in
Figure 6b, the green color indicates a good or very good student performance.
Average or acceptable result is depicted in yellow color, domain intervention is
recommended in this case. Finally, mandatory domain intervention is displayed in red, in
order to ensure that students that have difficulties receive the help they need before
the regular courses start.</p>
          <p>For each particular domain, topics performance is presented in specific detail by
using the same color-code. Figure 6c exemplifies the six topics used for determining
the student performance regarding the study habits domain. This figure illustrates the
scenario in which the student performed properly in three topics (peer-social
relationships, study motivation and time management) and acceptable in the other three
(concentration, memory and test taking strategies). This type of graph is used as a guide
that may be used in helping the student select appropriate support. At the same time,
the core system of the preliminary evaluation application uses this information to
determine and habilitate the specific sections in which the students need additional
assistance; turning the topics name into links to the precise instruction section that
could be available as a service provided by a different system hosted in a different
institutional node.</p>
          <p>Since the MDLE has the capability to assign specific learning activities to students,
the teacher view is mainly intended to provide both individual and group view of
knowledge and academic behavior. An example of the group information a teacher
can see is presented in Figure 7. In this case, this graph corresponds to the self-esteem
evaluation of a group of about 100 freshman students that used the system last
summer. Observations on the upper side are students identified with a very good
selfesteem level. On the other hand, those examinees on the lower side of the graph were
identified as students with a low self-esteem. This is interesting information that can
be used by teachers to pay special attention to some specific students. At the same
time, this information can be used by other systems within the MDLE environment, to
automatically implement motivational strategies to encourage the participation of
students with low self-esteem.
The Mathematics module is responsible for characterizing the student knowledge
level and the different exercises complexity using a series of mathematical formulas
based on the Item Response Theory (IRT) model [18]. Then, both the student and the
teacher are offered the possibility of graphically accessing the information generated.
The exercises are categorized by their difficulty. The complexity of an exercise will
be greater when the student needs more capacity to solve it [19]. This parameter is
calculated using the following formula:
_ =
_
_
 ___
 __ℎ_
 =
 =
_
_
= 1+exepx⁡(p −⁡(−))</p>
          <p>Students are characterized by their skill, efficiency and likelihood of success in an
exercise. The skill is the ability of a student to solve an exercise successfully and
efficiency is the ability of a student to solve an exercise successfully in the shortest
possible time. The efficiency and the skill are calculated as shown in formulas below:
(1)
(2)
(3)
(4)</p>
          <p>For the likelihood of success in an exercise the IRT model is used. The IRT is a
probability that will tell us what possibilities a student has to successfully complete a
specific exercise [18]. This information will be very useful to know what exercises
should be shown to a student and increasing their difficulty as long as the student's
skill is growing. For the calculation of the IRT the Rasch model was used, where the
probability is defined as shown in formula 4 (where θ represents the student’s skill
and β is the level of difficulty of the exercise) [20]:</p>
          <p>In order to display the information visually, a web module has been developed
where users can navigate between the different tabs and access different configurable
graphs. In addition, has been developed a system of credentials (teacher and student
roles), so that, depending on the person accessing the analytics module, different
privileges are available. In this way, the information shown to a teacher is different than
that for students. While the student can visualize only his own information, teachers
are able to analyze individual and group learning performance.</p>
          <p>Some examples of the graphs that students or teachers can see are shown below.
On the left side of Figure 8, the graph compares the difficulty of an exercise with all
the exercises of the same topic (available for the teacher role). And on the right side
of Figure 8, the graph compares the ability of a particular student with the rest of the
people enrolled in a particular course (available for the student and teacher roles). At
the same time, dashboards can be generated by combining graphical information from
this educational system with external visual aids, such as the one presented in Figure
7.</p>
          <p>In this paper, we have presented MDLE, a multidomain computer-based learning
environment as a proposal for students’ data sharing among interconnected
educational software systems. The main idea is to combine a set of educational systems,
hosted in different locations, and their generated users-data to implement a
comprehensive learning analytics service. Each educational system integrated in the proposed
environment could be a provider and/or consumer of preprocessed students’
information. Enhancing nodes collaboration will provide a more comprehensive
understanding of the students learning activity and facilitate service and data reuse. As a
demonstration of the MDLE interoperability, we described two educational
computerbased systems that were integrated and evaluated in this environment.</p>
          <p>The presented version of the proposed environment will be subsequently
supplemented based on two main factors: recommendations of users and technical
improvements. First, stakeholders’ opinion (students and teachers) is critical in order to
understand the type of learning analytics views that this environment can facilitate to
enhance the learning process. We are considering conducting further investigation
about the benefits of this environment interoperability, generating dashboards by
integrating learning analytics views from systems attending multiple domains. Regarding
the technical implementation of the proposed environment, we are working on the
design and evaluation of MDLE using the OAuth standard as communication and
authentication protocol. We are intended to apply the OAuth protocol to use a
complementary method for data transfer between nodes, instead of using a centralized
database; this will require the implementation of a communication protocol used for
data transfer.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>Work partially funded by the CONACYT project under grant no.
PDCPN201401/247698; and by the PRODEP project, supported by the 2015 call for the
Integration of Thematic Networks of Academic Collaboration. This work has been also
partially funded by the eMadrid project, funded by the Madrid
Regional Government with grant No. S2013/ICE-2715, and the RESET
project (grant No. TIN2014-53199-C3-1-R) and the SNOLA project (grant
No. TIN2015-71669-REDT), projects funded by the Spanish Ministry of
Economy and Competitiveness.
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