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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Towards a Methodology and a Toolkit to Analyse Data for Novices in Computer Programming</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Tatiana Person</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ivan Ruiz-Rube</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Juan M. Dodero</string-name>
          <email>juanma.doderog@uca.es</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Escuela Superior de Ingenier a (Puerto Real, Cadiz), University of Cadiz</institution>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <abstract>
        <p>The incorporation of mobile applications in diverse environments generates a large amount of information resulting from the interaction of users with these mobile applications. The analysis of this information can facilitate decision-making or evaluation of the process for the professionals, allowing for improved results or the detection of certain patterns. There are multiple technologies for data analysis that can be applied to analyse the captured information. However, the development of mobile applications that incorporate these features is not trivial for a user who does not have the appropriate programming skills. In addition, decision-making to select the data analysis technology to be applied in each situation is di cult for this type of users. In this work, a methodology is presented to help people without appropriate programming skills in the above process. Finally, this methodology is being applied in a visual authoring tool to enable the users to create mobile applications that incorporate this features.</p>
      </abstract>
      <kwd-group>
        <kwd>Authoring tools</kwd>
        <kwd>Data analysis</kwd>
        <kwd>Learning analytics bile learning</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        MoAccording to the 2017 Ditrendia report [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], nowadays 66% of the world's
population has a smart-phone and the use of mobile applications represents 60% of the
time spent in the digital world. Based on the above data, we can conclude that
mobile applications are playing an increasingly important role in people's daily
lives. Existing digital content repositories, such as Google Play Store or App
Store, contain mobile applications in a variety of topics: applications for
peopleto-people communication, to entertainment, to life-style control and monitoring.
Mobile applications also emerged for di erent educational purposes: explaining
speci c topics or concepts, evaluating students, conducting laboratory
experiments, solving exercises collaboratively, learning foreign languages, etc.
      </p>
      <p>
        New ways of interaction between users and mobile devices such as the use of
elements for verbal interaction through the use of voice commands and
soundtracks [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], touch through the use of tactile surfaces and haptic devices [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], or
gesture by capturing human movement [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] are generating a large amount of
      </p>
      <p>
        Copyright © 2018 for this paper by its authors. Copying permitted for private and academic purposes
data [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. This data may be collected and later processed using Learning
Analytics (LA) and Educational Data Mining (EDM) techniques. Which allow us
to evaluate the experience and learning of users, as well as the usability of the
applications themselves [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ],[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], because the data can be transformed into
information and knowledge. Thus, several speci cations related to learning analytics
have been developed, such as Learning Tools Interoperability (LTI), to facilitate
the integration of e-learning tools; Experience API (xAPI), for the publication
of meta-data on real learning activities; or the most recent Caliper Analytics, for
data extraction and computation of metrics [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>
        In addition, these data can be analysed using the techniques covered by the
Big Data Analytics concept. The choice for one of these techniques will depend on
the characteristics contemplated in the context in which the data are analysed,
including the time that they were created [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. First, if the analysis of the data
generated in the past and stored in databases at the time of analysis is required,
relational database analysis, non-relational database analysis or OLAP analysis
may be used. Second, if the analysis of data generated during the analysis is
needed, stream analytics or complex event processing may be applicable. Finally,
if the analysis of data generated in the past and stored in the database at the time
of the analysis is demanded, but this analysis intends to predict the behaviour
or some future data characteristic, machine learning or deep learning may be
applicable.
      </p>
      <p>
        However, it is important to be aware of the di culty of conducting large
amounts of data analysis for users without extensive programming knowledge.
In this sense, the use of environments that support such users to perform these
types of operations is essential. Therefore, the main aim of this research is to
design a methodology that allows non-technical users to make use of this type
of analysis of large amounts of data independently, without requiring IT experts
to do this work for them. Based on the results described in [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], the author
concludes that possibly one of the main challenges of the data processing
lifecycle is having the ability to choose which tools and technologies to use e ectively
and e ciently. In addition, the necessary characteristics for the construction of
this type of architecture must also be considered [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
      </p>
      <p>Finally, the rest of the work is structured as follows: in the second section
the background is presented. The third section presents the initial version of the
designed methodology. The fourth section introduces the implementation of the
VEDILS components to provide the functionalities proposed by the
methodology. Finally, the conclusions of this work are presented in section ve.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Background</title>
      <p>Firstly, visual authoring tools are computer applications that facilitate the
creation, publication and management of multiple materials in digital format.
Normally, these tools model software development processes that require IT experts
to be able to execute them, allowing non-expert users to do this work with
the support of the automation provided by the tool. For example, with Google
Forms 1, non-web development experts can easily create web surveys that they
can share and then analyse the data they collect. There are application authoring
tools that use a visual language to create these applications, such as Scratch2,
MIT App Inventor 3, Pocket Code4 or VEDILS 5. On the other hand, there are
application authoring tools that use a textual language, such as Microsoft Touch
Develop6, Upplication7, GameSalad 8 or Alice9.</p>
      <p>
        Secondly, context can be de ned as a fragment of information that can be
used to characterise the situation of a participant in an interaction[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. In
addition, by detecting context information, applications can present useful
information related to the context of users and adapt their behaviour to changes in the
environment[
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. In the [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] work, the following are de ned as context properties:
domain context, location context, data context and user context.
      </p>
      <p>Finally, the technologies that can be used for data analysis can be classi ed
according to when the data to be analysed is created, as follows:
{ Technologies for Past Data Analysis: technologies to analyse previously
created and stored data.</p>
      <p>Relational database analysis : First, relational DBMS (Database
Management System) are storage systems that comply with the relational model.
In this type of system, the databases are composed of several tables and
relationships with unique names. The relationships between tables are
made through the use of primary and foreign keys. On the other hand,
the SQL language is used to manipulate and consult the information
stored in a relational DBMS. Some of the most used relational DBMS
are: MySQL10, Oracle11 or PostgreSQL12.</p>
      <p>Non-Relational database analysis : On the other hand, non-relational
DBMS require less powerful machines, facilitating horizontal
scalability; improving system performance requires only the addition of new
nodes. They can store large amounts of data, through their distributed
structures and do not generate bottlenecks. On the other hand, the most
popular non-relational DBMS today include the following: Redis13,
Cas1 https://www.google.es/intl/es/forms/about/
2 https://scratch.mit.edu
3 http://appinventor.mit.edu
4 https://share.catrob.at/pocketcode/
5 http://vedils.uca.es
6 https://www.touchdevelop.com
7 https://www.upplication.com
8 http://gamesalad.com
9 https://www.alice.org
10 https://www.mysql.com
11 https://www.oracle.com
12 https://www.postgresql.org
13 https://redis.io
sandra14, CouchBase15, HBase16, MongoDB 17 and AllegroGraph18.
Multidimensional database analysis : OLAP (On-Line Analytical
Processing) is considered as a solution used in Business Intelligence that allows
the user to extract and visualise data from a variety of points of view. To
perform this type of analysis, multidimensional structures are used,
represented metaphorically as a cube (OLAP cube) whose cells correspond
to events that occur in the business domain. Currently, existing tools
that incorporate the ability to perform OLAP analysis include: Pentaho
BI 19, Dundas BI 20, Sisense21, Domo22 and Tellius 23.
{ Technologies for Present Data Analysis: technologies to analyse data
that are created during the course of the analysis.</p>
      <p>
        Stream analytics : With reference to Stream analytics technology, the
tools for data transmission and the tools for data processing in
streaming should be considered. First, as tools for the transmission of data, the
Message Queuing or Pub-Sub Messaging systems must be considered,
which are used as asynchronous intermediary systems, implementing the
publishing-subscribing paradigm. Typically, these systems decouple
different components of an architecture. Popular message queuing systems
include: Apache Kafka24, RabbitMQ 25 and ActiveMQ 26. On the other
hand, streaming data processing tools work with continuous and
nonpersistent data streams. This data can come from sensors or publications
on social networks, for example. Currently, streaming data processing
tools include: Apache Flink 27, Apache Spark 28 and Apache Storm29.
Complex Event Processing : Complex event processing (CEP) systems
di er from streaming processing systems in that they associate
semantics with the information they are processing, which are noti cations
of events occurring in the external world and observed in information
14 http://cassandra.apache.org
15 https://www.couchbase.com
16 https://hbase.apache.org
17 http://www.mongodb.com
18 https://allegrograph.com
19 http://www.pentaho.com
20 http://www.dundas.com/dundas-bi
21 https://www.sisense.com
22 https://www.domo.com
23 http://www.tellius.com
24 https://kafka.apache.org
25 https://www.rabbitmq.com
26 http://activemq.apache.org
27 https:// ink.apache.org
28 https://spark.apache.org
29 http://storm.apache.org
sources. The CEP engine is responsible for ltering and combining such
noti cations to understand what is happening in terms of complex events
(high-level events composed of the combination of simple events) and
then notifying customers subscribed to these alarms[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Currently,
complex event processing tools include Apache Spark, Apache Flink and
Esper 30.
{ Technologies for Future Data Analysis: technologies to analyse data to
be created later.
      </p>
      <p>
        Machine Learning : can be de ned as a mechanism for searching for
patterns and creating intelligence on a machine enabling you to learn. This
means that you will be able to solve problems more correctly or e ciently
in the future based on your experience, just as in humans. Machine
Learning algorithms can be classi ed according to the type of learning
problem they solve in: classi cation, grouping, regression, optimisation
and simulation. On the other hand, the analyses applied using Machine
Learning can be classi ed according to the behaviour of the algorithm
in: Supervised learning, Unsupervised learning, Semi-supervised learning
or Reinforcement Learning[
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Currently, tools for applying Machine
Learning algorithms include: Apache Mahout 31, R32, Julia33, Apache
Spark and Apache Flink.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Methodology</title>
      <p>
        This work proposes the rst version of a methodology to assist in
decisionmaking when choosing a technology for data analysis. Learning analytics is an
emerging area within e-learning and generally consists of the following stages:
capture, report, predict, act and re ne[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Following the above, this methodology
should allow programming novices to perform these steps without the assistance
of computer experts. In addition, support should also be provided so that they
can easily select what type of technology to apply to the reporting of the data
they have captured. Figure 1 shows a diagram with possible decisions. The
following context characteristics have been used to decide on the use of each of the
technologies:
{ Temporal instant : Temporal instant when the analysis is performed.
{ Data structure: Expected characteristics in the recorded data structure.
{ Query format : Expected characteristics of the queries to be made.
30 http://www.espertech.com
31 http://mahout.apache.org
32 https://www.r-project.org
33 https://juliacomputing.com
To enable the data analysis to people without programming knowledge, the
proposed methodology has been applied in a visual application authoring tool.
VEDILS is an environment based on MIT App Inventor 2 to easily develop
multimodal and interactive learning scenarios. The platform includes a view where the
user can design the user interface and a view (Blockly-based editor) where they
can de ne the behaviour of the elements included in the applications. VEDILS
provides a set of additional features that can be integrated with those already
provided by MIT App Inventor 2. Features such as augmented reality, virtual
reality, gestural interaction and learning analytics, among others are available. The
set of components implemented for this research are described below. Currently,
the implemented components only support the past and present data analysis
functionalities of the methodology.
      </p>
      <p>Enabling the recording of information to analyse
First, we have developed the ActivityTracker component, which aims to
facilitate the process of recording information related to interactions between users
and mobile devices and nally register it in a database. Currently, the stores
supported by this component are Google Fusion Tables (SQL) and MongoDB
(NO-SQL). In addition, this component allows the streaming processing of the
sent data. The above options can be con gured from the ActivityTracker
component properties (see Figure 2).</p>
      <p>On the other hand, ActivityTracker allows automatic registration every time
a function is invoked, a property is accessed or an event is triggered from any of
the existing VEDILS components while using the application (see Figure 3a). In
addition, it allows you to send data with a semantics previously de ned by the
application designer (see Figure 3b).</p>
      <p>(b) Blocks to record user-speci c noti cations</p>
      <p>Fig. 3: Blocks to record noti cations using ActivityTracker component
4.2</p>
      <p>Enabling to query the recorded information
Secondly, the objective of the components ActivitySimpleQuery and
ActivityAggregationQuery is to allow the consultation of the data recorded in the database
by the component ActivityTracker. The ActivitySimpleQuery component allows
for simple queries, i.e. queries that include data selection and ltering (select ).
On the other hand, the ActivityAggregationQuery component allows you to
perform more complex queries, in which you can group data (groupBy ) and perform
metrics on them, such as: arithmetic mean, sum, maximum, minimum or number
of elements. The above options can be con gured from the ActivitySimpleQuery
and ActivityAggregationQuery components properties (see Figures 4a and 4b).
The queries made can be conventional queries (see Figure 5a) that are executed
only once or streaming queries (see Figure 5b) that are executed iteratively in
time intervals.</p>
      <p>(a) Properties of
ActivitySimpleQuery component
(b) Properties of
ActivityAggregationQuery
component</p>
      <p>Enabling the representation of obtained-query results
The purpose of the Chart and DataTable components is to present a speci c
data set in graphical or tabular form, which will be the result of a previous query
using the ActivitySimpleQuery and ActivityAggregationQuery components. The
Chart component enables you to represent the data in graphic format (row,
column, etc.). The above options can be con gured from the DataTable and
(a) Blocks to process
conventional queries</p>
      <p>(b) Blocks to process streaming queries
Chart components properties (see Figures 6a and 6b). And on the other hand,
the DataTable component allows you to represent the data in table format (see
Figure 7).</p>
      <p>(a) Properties of
DataTable component
(b) Properties
Chart component
of</p>
      <p>Fig. 6: Properties to con gure the DataTable and Chart components
The constant increase in the number of mobile devices can be used to improve the
processes executed in multiple areas, analysing the data produced through the
incorporation of mobile applications for this purpose. This would be positively
accepted by the population, as approximately half of the time spent in the digital
world is directly linked to the use of mobile applications. On the other hand, the
use of speci c-purpose applications can generate a lot of information that can
then be analysed using Learning Analytics techniques.</p>
      <p>However, it is important to remember that the creation of speci c-purpose
applications is very di cult for people with limited programming skills. This
work presents a methodology to help programming novices decide what type of
data analysis technology to decide in each situation.</p>
      <p>As future work, the implementation of the rest of the LA components in
VEDILS will be carried out. In addition, a usability assessment will be conducted
with users to evaluate the e ectiveness of the proposed methodology. Finally, a
virtual assistant will be implemented to provide the necessary support to follow
the methodology from VEDILS.</p>
    </sec>
    <sec id="sec-4">
      <title>Acknowledgements</title>
      <p>This work has been developed in the VISAIGLE project, funded by the Spanish
Ministry of Economy, Industry and Competitiveness with ref. TIN2017-85797-R.</p>
    </sec>
  </body>
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