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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Context data learner model for classroom and intelligent tutoring systems</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Janis Bicans</string-name>
          <email>cans@r</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Riga Technical University</institution>
          ,
          <country>Latvia Jani s. Bi</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Nowadays technological advancement enables multiple education scenarios, like online learning and technology enhanced classroom learning. Both of these scenarios share a common level of knowledge about the learner and his or her learning preferences. This knowledge is limited and in most scenarios gathered via a learner survey. This situation limits system capability on delivering individualised learning experience as the learner sometimes is not able to define his or her learning style, actual preferences and other aspects. Learning session and learner context data enable more advanced adaptation in intelligent tutoring scenarios and deliver new analytical capabilities to the trainer in classroom learning. Learning context data can be captured via various means and from multiple data sources, like education institution systems and physical sensors. This paper proposes the learner context data model attributes identifies the data sources to fill this model and identifies possible techniques to enable this process automation.</p>
      </abstract>
      <kwd-group>
        <kwd />
        <kwd>Learner context data model</kwd>
        <kwd>context data acquisition</kwd>
        <kwd>learning process</kwd>
        <kwd>intelligent tutoring system</kwd>
        <kwd>context awareness</kwd>
        <kwd>learner analytics</kwd>
        <kwd>learner model</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Personalised learning has a potential to improve learning process and overall learning
results [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Personalization maybe achieved via learning content
personalization and individualised learning strategy application. Therefore, it is important to
gain well applicable and trustful information about the learner, including, its previous
experience and knowledge level, learning style, learning preferences and learning
habits and create learner model. Contextual information qualifies as one of the sources for
learner model creation and could be used for an online and in classroom learning [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        The Intelligent Tutoring Systems (ITS) [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] in most scenarios operate as a
recommender system that gathers appropriate and requested learning material from the
learning object/ training material repository and/or provides other recommendations about
the learning material application. In more advanced scenarios, ITS assess learner’s
knowledge and based on the results adapt tutoring material difficulty level [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. If the
context aware system is able to identify learners who are working on a similar learning
activities, the system can suggest suitable peer learners to collaborate with [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        Any learning session happens in defined, describable and observable environment,
which might be either physical or virtual, e.g., e-learning system. Such environment
could be an educational institution, corporate environment, home or any other place
that is suitable for education. Learning from process perspective [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] could be a
coursesteered, self-steered or context-steered. At universities and companies, we can find the
course-steered learning as the core learning process. This learning process follows
strictly defined course structure and there are very limited possibilities to provide
individualised learning. Context-steered learning additionally to textual, graphical and
multimedia learning objects [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] may use available human resources (problem domain
experts, colleagues and trainers) and enable dynamic such resource management and
utilisation.
      </p>
      <p>
        To describe learning environment with various contexts Schmidt [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] has identified
the following activities that should be performed to enable context aware learning. In
other researches these activities are essentially the same, but have different wording
[
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]:
•
•
•
      </p>
      <p>Context capturing. This activity collects information about the learner and the
learning session conditions. For example, assigned tasks and personal information that
is relevant to learning process, like learner’s previous experience, individual goals,
cognitive style and other aspects. The context can be captured from multiple
sources, therefore, it should be managed in a way that several applications can view,
modify and update the context in a mutually enriching way.</p>
      <p>Development and application of context aware methods. Current online learning
platforms (both academic and enterprise) support continuous learning and have a
strictly defined learning path. However, context aware systems enable on-demand
learning by taking only context relevant learning objects. For example, when learner
is performing some task and identifies that there is a need for additional information,
the context aware system could assist and assess the situation and look for
applicable and suitable learning material that is not necessarily a long lasting curriculum,
but might be a short how-to guide on a particular subject. The context aware systems
have great application potential in work/enterprise environment, where companies
might have multiple knowledge bases and other information sources. Wiki pages,
knowledge management systems are common systems for almost any company and
they might contain large number of tagged information that is almost ready for
context-aware applications.</p>
      <p>Context-aware resource preparation. This activity is responsible for tutoring content
preparation for further application in context-aware systems. The objective of this
activity is to create context application-ready tutoring material including resource
relationship definitions.</p>
      <p>
        After context is captured, it is important to identify context quality level. If context
quality is low, it will not be applicable in classroom and/or intelligent tutoring systems.
Bellavista et al. [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] have identified, that context quality is measured by the following
three parameters: context data level of trust, context data precision and context data
age. Consequently, capturing, storing and verification of these parameters should be
included in any context and assessed each time when new context is created/captured
or existing context is updated. These parameters, additionally to context quality
assessment, could be used for context conflict management. Each context weight/significance
might be based on a combination of all three parameters.
      </p>
      <p>
        The goal of this paper is to create context aware learner model and identify
corresponding context data sources for the analysed hybrid learning scenario, where
traditional classroom training is provided with additional learning materials available via
online ITS prototype [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. The research contribution of this paper is twofold.
• First, context learner model is proposed for a particular hybrid learning environment
(classroom and virtual) to support analysed learning scenario.
• Second, empirical contextual information data sources at Riga Technical University
are identified and analysed.
      </p>
      <p>The paper is organized as follows. Section II discusses the context modelling aspects.
Section III presents the proposed context model. Section IV discusses the empirical
results.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Context Modelling</title>
      <p>
        For any entity or process we can find unlimited amount of contexts and consequently
create unlimited number of context models. This situation requires to identify context
importance and relevance for a particular application and have a good understanding
about the context and the context elements. Perera et.al. [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] have adopted various
context model interpretation and context attributes to define the context model and the
context attribute. “A context model identifies a concrete subset of the context that is
realistically attainable from sensors, applications and users and able to be exploited in
the execution of the task. The context model that is employed by a given context-aware
application is usually explicitly specified by the application developer, but may evolve
over time. [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]” And context attribute as “an element of the context model describing the
context. A context attribute has an identifier, a type and a value, and optionally a
collection of properties describing specific characteristics [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].”
      </p>
      <p>
        Any context model can be static or dynamic, have its own lifecycle, level of trust,
relationships with other contexts, timelines and other attributes. Past research
approaches demonstrate generic context model development where context is classified
in three groups: user context, things context and system context [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Some context
aware systems use location information for various adaption scenarios [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. For
educational domain the attributes from all three kind of contexts are relevant.
      </p>
      <p>
        Context modelling can be done by several techniques. Straong and Linnhoff-Popien
[
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] have surveyed most popular context modelling techniques like Key-Value
Modelling, Markup Scheme Modelling (Tagged Encoding), Graphical Modelling, Object
Based Modelling, Logic Based Modelling, Ontology Based Modelling. Any of
mentioned modelling techniques has its own benefits and drawbacks. The learner context
model proposed in this paper will be modelled by using object based modelling,
because the object based concepts are used to model data using class hierarchies and
relationships. Object oriented paradigm promotes encapsulation and re-usability and is
supported by modern object oriented programming languages. Previous software
development knowledge can be reused for system context aware system development and
integration. Moreover, object based modelling is suitable to be used as an internal,
nonshared, code based, runtime context modelling, manipulation and storage mechanism
[
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Lack of built-in reasoning capabilities is not important at current research state as
the context components will be integrated with other system components and
consequently, reasoning will be delegated to the other system components.
      </p>
      <p>For situations where a single context is being used by multiple entities, context aware
system should be able to identify to which entity this context applies, how to present it
(order, structure, etc.), therefore, pre-defined application scenario and/or entity
identification mechanisms should be implemented in the system.</p>
      <p>
        Based on a context model application domain, they may describe general
information about the context and a context structure with corresponding relationships, or
be very specific and describe in details each context element internal structure,
behaviour and relationships with other context element. Which level of detail to choose
depends on the application domain and author’s/experts beliefs. Modelling can be done
in a various levels- conceptual, logical and physical. Physical modelling is not needed
when context components are integrated into existing system or this level is replaced
with system architecture. However, it is required to define how defined context results
will integrate into existing or newly created system or its components. In the learning
domain context modelling could be done in several directions; learning object context,
pedagogical context, student model context, learning session context, learning
environment context. Any of these contexts at some degree could be used to facilitate distance
learning and classroom process. This research focuses on ITS and classroom learning
hybrid scenario learner context model. Therefore, the proposed model is the first
iteration of continues model development and at this stage may not contain all possible
learning domain contexts and context attributes. The proposed model is based on a
student model proposed by Lukasenko [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], which contains the following information
categories: Contact information, learner learning style, learner current state (mood, mental
state, face expression, physiological state) current level of knowledge and skills, learner
objectives, learning progress, used learning material, user interface setup.
      </p>
      <p>All context categories and attributes are considered with the following parameters
and their description is given in Table 1.</p>
      <sec id="sec-2-1">
        <title>Granularity/ Resolution</title>
      </sec>
      <sec id="sec-2-2">
        <title>Description</title>
        <p>tively by the system
author or based on
calculated results
Describe level of details.</p>
      </sec>
      <sec id="sec-2-3">
        <title>Information/Data source confidence rank Data age</title>
      </sec>
      <sec id="sec-2-4">
        <title>Describes information source confidence level Describes data age</title>
      </sec>
      <sec id="sec-2-5">
        <title>Metric</title>
      </sec>
      <sec id="sec-2-6">
        <title>Group or individual students, each minute, hour, second, etc. Rank or rating</title>
      </sec>
      <sec id="sec-2-7">
        <title>Date and/or time</title>
        <p>Each context element has its own data source that needs to be identified. This is
analytical activity where operation environment (virtual and/or physical) iteratively is
reviewed as some data sources should be changed during system operation. After all
available information about operation environment is gathered it needs to be evaluated
by following several steps: 1st step identifies all physical and virtual sensors. As a
virtual sensor might serve existing service, database, it system or application. 2nd step in
case if context is composed from multiple sensors, a single logical sensor is created,
where author defines sensor data merging/transformation mechanism and result data
structure of this sensor. 3rd step defines data source reliability and confidence rank,
desired data precision and granularity.
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Proposed Context Model</title>
      <p>The proposed context model is an object that consists of several sub objects which
corresponds to the contexts/ context dimensions and is designed to fill in and/or verify
learner model attributes. This model for classroom learning will provide more detailed
information to trainer for further and more detailed student result analysis and for ITS
model it will serve as additional source of information for personalised learning content
delivery. The model will describe various aspects of student model. As a first step the
set of learner model attributes that could be filled in from context models is proposed
(see Table 2). Each learner model category represents learner context sub contexts
which are part of the proposed context model.
model</p>
      <sec id="sec-3-1">
        <title>Attribute</title>
      </sec>
      <sec id="sec-3-2">
        <title>Description</title>
      </sec>
      <sec id="sec-3-3">
        <title>Name/Surname/IDs E-mail address</title>
      </sec>
      <sec id="sec-3-4">
        <title>Learning style</title>
      </sec>
      <sec id="sec-3-5">
        <title>Attributes to uniquely identify learner in the system Parameter for communication with the learner</title>
        <p>A learner’s learning style (theory
oriented, task oriented, problem solving
oriented)
Learner
category
Contact
information</p>
      </sec>
      <sec id="sec-3-6">
        <title>Personality characteristics Learner category</title>
        <p>Current
knowledge
skills
Use of system</p>
      </sec>
      <sec id="sec-3-7">
        <title>Learning progress</title>
      </sec>
      <sec id="sec-3-8">
        <title>Knowledge level</title>
        <p>and in a problem
domain
Topics reviewed/
tasks completed
in a course
Attempts made/
time spent
model</p>
      </sec>
      <sec id="sec-3-9">
        <title>Attribute</title>
      </sec>
      <sec id="sec-3-10">
        <title>Description</title>
      </sec>
      <sec id="sec-3-11">
        <title>The learner’s level of knowledge in the</title>
        <p>problem domain before beginning of a
course
The course topics that the learner has
viewed/studied. The tasks that the learner
has solved.</p>
        <p>The number of attempts committed by the
learner to solve a task, and the time spent
on studying a topic
3.1</p>
        <p>Identified Data Sources
The proposed context aware learner model attributes could be filled in either manually
by system author or by semi-automatic/automatic way based on data of another system
or data store. Analysed learning scenario is taking place at Riga Technical University
where classroom training is supported by ITS prototype. University as educational
institution has multiple IT systems with various functionality. For this scenario particular
interest is in an annual survey system, study system that stores information about the
learner’s performance, ITS prototype and e-learning platform Moodle (see Table 3).</p>
      </sec>
      <sec id="sec-3-12">
        <title>Data source ITS prototype</title>
      </sec>
      <sec id="sec-3-13">
        <title>University survey system</title>
      </sec>
      <sec id="sec-3-14">
        <title>University study system</title>
      </sec>
      <sec id="sec-3-15">
        <title>Moodle</title>
        <p>The attributes of the proposed learner context model are analysed according to the
parameters listed in Table 1, namely, attribute precision, reliability,
granularity/resolution, data source confidence rank, data age and sensor type:
•
•
•
•
•</p>
        <p>Learner identification information (name, surname, IDs, email address). This
combination of attributes is precise, reliable, verifiable and detailed. The data for these
attributes come from university study system which is a fully trustful data store. The
only exception is the email address, that is subject of occasional change.
Information is captured via virtual sensors.</p>
        <p>Learning style. The learning style is of low precision, subject of rapid change, hard
to verify and not detailed. Learning style is based on various primary and secondary
contexts and data interpretation algorithms. Data sources for learning style are
multiple mostly system logs. In this research these data sources are ITS prototype and
Moodle log as well as annual learners’ survey. The information is captured from
various virtual and logical sensors.</p>
        <p>Knowledge level in a problem domain. The knowledge level is a subject of change
and has medium level of precision; information is reliable depending on the type of
knowledge assessment level of information resolution may vary. Data source
confidence rank is from medium to fully trustful as the sources of information are
university study system (fully trustful) and ITS knowledge assessment modules where
level of trust is medium. Similar to learning style attribute, the data may come from
virtual and logical sensors.</p>
        <p>Topics reviewed/ tasks completed in a course. This attribute is based on systems
logs (ITS and Moodle), is trustful, precise and has high level of details. Data source
is reliable and data is up-to-date. Information comes from virtual sensors.
Attempts made/ time spent. This attribute is similar to topics reviewed/tasks
completed and shares the same attribute characteristics.
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Results and Discussion</title>
      <p>Research discussed in this paper follows the 3 main context aware learning activities
(see Section 1) by defining context capturing aspects, identifies context data source
level of trust for further application scenarios in the classroom and intelligent tutoring
system supported learning. The analysis of empirical available data set (see Table 3)
showed, that it is possible to use this contextual data for several proposed learner model
attributes semiautomatic/automatic filling. However, to automate this process there is
a need for an initial effort on a data source annotation, metadata preparation, context
models and context relationship definition. More advanced automation scenarios could
be enabled by implementing reasoning techniques. For a small number of learners’ and
where high level context model description is satisfactory, learner context model can
be filled with data manually by the trainer and/or expert. For the analysed context
application scenario corresponding tooling is required. Additionally, the analysed data
contain verifiable information, for example, the number of attended classroom lectures,
learner’s employment status that might affect overall learner performance and provide
additional information about the learner’s level of knowledge ( for example, experience
with programming languages and other relevant information), therefore, some physical
sensor and/or software for learner direct and indirect tracking solution/system and
integration with other external systems (for example, employment and industry related
skill set might come from LinkedIn social network) is required.</p>
    </sec>
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