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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Using Conceptual Models in Research Methods Courses: An experience using iStar 2.0</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Marcela Ruiz</string-name>
          <email>m.ruiz@uu.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Fatma Başak Aydemir</string-name>
          <email>f.b.aydemir@uu.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Fabiano Dalpiaz</string-name>
          <email>f.dalpiaz@uu.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Information and Computing Sciences Utrecht University</institution>
          ,
          <country country="NL">the Netherlands</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2017</year>
      </pub-date>
      <fpage>48</fpage>
      <lpage>57</lpage>
      <abstract>
        <p>Conceptual modelling languages are typically taught in graduate and postgraduate information systems programs. In the specific case of postgraduate information systems students, the lecturer has the opportunity to exploit conceptual modelling for educational purposes that go beyond learning how to apply the modelling paradigm or specific languages. In this paper, we report on our employment of the recently proposed iStar 2.0 in the master-level course Advanced Research Methods at Utrecht University in the Netherlands. During this course, the students conducted a design science project where iStar 2.0 artefacts are evaluated in an experimental setting. We present the course (intended learning objectives, learning materials, etc.), we explain how we employed iStar 2.0 therein, and we discuss our teaching experience including lessons learnt.</p>
      </abstract>
      <kwd-group>
        <kwd>iStar 2</kwd>
        <kwd>0</kwd>
        <kwd>education</kwd>
        <kwd>research methods</kwd>
        <kwd>experimental design</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Teaching conceptual modelling poses major challenges for the current educational
programs in information and computer sciences. In this context, the lecture room lets the
students learn novel conceptual modelling languages, use tools and techniques for the
specification of conceptual models, apprehend guidelines and algorithms for
transforming conceptual models into software systems, and come across methods that facilitate
the practical application and evolution of conceptual modelling languages [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. The
variety of artefacts to be taught in courses related to conceptual modelling poses an
interesting teaching dilemma: what are the appropriate methods for providing education
about each artefact to bachelor and master students?
Given the complexity of the theoretical concepts related to conceptual modelling, it is
common practice in higher education to teach business process modelling, databases,
and software engineering in bachelor courses; while keeping goal analysis,
meta-modelling, and enterprise modelling for master-level or advanced bachelor courses.
Furthermore, students are taught how to construct models using a conceptual modelling
language, but are hardly educated to reflect on the theoretical and practical challenges
that researchers encounter when building a language or related artefact. This may create
the false myth that conceptual modelling research is only about creating models.
For goal modelling, and particularly for the iStar framework [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] different experiences
have been reported for bachelor [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], master [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], and mixed courses [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The variety
of iStar artefacts (methods, modelling tools, transformation guidelines from iStar
models from/to other conceptual models, etc.) offers the opportunity to establish different
settings where the iStar framework can be taught, exploited, and studied [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
The Advanced Research Methods (ARM) course is a master-level course offered within
the Department of Information and Computing Sciences at Utrecht University, the
Netherlands, which is attended by circa 60 students per academic year. The first author
of this paper redesigned this course for the period 2016-2017 by incorporating the
Design Science method as a main component of the course [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Design Science is a
research method for the design and investigation of artefacts in context, and prescribe
engineering and empirical cycles for information systems projects in general.
For the ARM course, the students were made aware of research challenges concerning
goal modelling; they conducted a design science project with a basic design cycle and
a full empirical cycle, in which 4 existent iStar 2.0 [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] artefacts were investigated in an
experimental setting. During the ARM course, the students took the roles of researchers
and experimental subjects. Thus, we repot on our teaching experience where we
employed conceptual modelling artefacts in a research methods course; and not in the
conventional information systems and requirements engineering courses where the focus
is on model building. Through this paper, we make the following contributions:
 Promoting the use of conceptual modelling in teaching environments.
 Reporting on the design of four comparative experiments in which existent iStar 2.0
artefacts have been used as experimental objects.
 Applying the design science method for the evaluation of iStar 2.0 artefacts in
classroom environments.
 Discussing the employment of iStar 2.0 as part of the teaching material for research
method courses in information systems programmes.
      </p>
      <p>Paper organisation. Section 2 presents the intended learning outcomes and activities
for the advanced research methods course; Section 3 describes the employment of iStar
2.0 during the ARM course; and Section 4 discusses lessons learnt and teaching
directions for adopting iStar in teaching environments.
2</p>
      <p>Intended learning outcomes and activities for the ARM course
The Master’s Programme in Business Informatics (MBI) at Utrecht University,
Department of Information and Computing Sciences, is a research master with an integrative
and multidisciplinary approach that trains future ICT Researchers, Analysts, and
Entrepreneurs. ARM1 is a compulsory course and one of the pillars of the MBI program. The
main objective of the course is to train the students to apply research methods, and give
the students the opportunity to play the role of researchers in information sciences.</p>
    </sec>
    <sec id="sec-2">
      <title>1 https://sites.google.com/view/arm16-17</title>
      <p>2.1</p>
      <sec id="sec-2-1">
        <title>Intended learning outcomes</title>
        <p>During the lectures and laboratory sessions, students gain skills to conduct research
projects, develop a researcher attitude, and acquire knowledge about research methods.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>The intended learning outcomes (ILOs) for the ARM course are listed in Table 1.</title>
      <p>To contribute to the successful achievement of ILOs 1 and 2, we provided students with
conceptual modelling artefacts that can be evaluated in a certain context. We selected
these among the iStar 2.0 artefacts and defined the following learning outcomes:
a) Knows how iStar 2.0, and social modelling languages in general, relate to other
conceptual and enterprise modelling languages;
b) Is able to comprehend existing iStar 2.0 models by having learned the language’s
syntax and semantics;</p>
    </sec>
    <sec id="sec-4">
      <title>c) Is able to create simple iStar 2.0 models.</title>
      <p>
        To achieve the learning outcomes a), b) and c), in the same spirit as [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], we designed
one lecture based on the iStar 2.0 tutorial given at ER 2016 and practical sessions that
contributed to an active learning environment. In the following sections, we describe
the activities, details about the background of the students and teaching materials.
2.2
      </p>
      <sec id="sec-4-1">
        <title>Activities</title>
        <p>For the ARM course, we designed different activities for one academic period of 10
weeks. Fig. 1 illustrates the main activities that took place during the 2016-2017
instance of the course. We kick-started the course with an introductory lecture, in which
we explained the main objectives and activities of the course. The same day, we asked
the students to fill in a demographic questionnaire with the purpose to get more insights
about their background and previous experience with research methods, requirements
engineering, conceptual modelling, goal modelling, business process modelling, and
design science. As a result, we found out that 53.7% of the students (29 out of 54
students) had experience with conceptual modelling thanks to bachelor courses like
information sciences and data modelling. One student reported to have industrial experience
with the application of conceptual modelling for software development.</p>
        <p>LECTURE:
EXPERIMENTAL
PLANNING &amp;</p>
        <p>OPERATION
LECTURE: EXPERIMENTAL
i* DESIGN</p>
        <p>DISTRIBUTION
OF TEAMS</p>
        <p>DRAFT OF
EXPERIMENTAL
EXECUTION</p>
        <p>RAW DATA
PER TEAM</p>
        <p>RESULTS OF
STATISTICAL</p>
        <p>TESTS
RESEARCH
QUESTIONS</p>
        <p>LECTURE:
STATISTICS</p>
        <p>DRAFT
DATA
ANALYSIS
POSTER</p>
        <p>LECTURES:
REPORTING &amp;
PACKAGING +
ELEVATOR
PITCH+POSTER
LECTURE:
DESIGN
SCIENCE</p>
        <p>FILLED
DEMOGRAPHIC DEMOGRAPHIC</p>
        <p>QUEST</p>
        <p>QUEST
1. KICK</p>
        <p>OFF
2. CREATE
TEAMS</p>
        <p>DRAFT:
TITTLE +
AUTHORS +</p>
        <p>ABSTRACT
4. SET UP THE</p>
        <p>DESIGN
SCIENCE</p>
        <p>PROJECT
S
M
A
E
T
L
L
A
S
M
A
E
T
L
A
U
D
I
V
I
D
N
I
9. COMPILE
RESULTS FOR
THE PROJECT
COMPILED DATA
PER PROJECT
notions about it. Regarding their professional experience, 42.6% of the students have
some professional experience; some roles to highlight are analyst, entrepreneur,
programmer, and junior consultant.</p>
        <p>For the next session (task 4 in Fig. 1), the students received the training to set up design
science projects and started to study the selected artefact for each team. For the iStar
lecture (task 5 in Fig. 1), the third author trained them to use iStar 2.0. For this, the
students received an interactive lecture of 2 hours plus 2 hours of practice. For the
practical assignment, the students took a scenario and modelled by using iStar. They were
in charge of identifying the main actors, define their goals, find their dependencies, use
intentional element links, analyse and evaluate alternative ways of fulfilling goals,
create the models pen-on-paper, and scan and send the models the same day. We checked
the models and the students received feedback to improve their models. The students
were committed to the activity for two main reasons: 1) they wanted to learn the details
about the artefact to evaluate, and 2) the models they prepared would serve as
experimental objects for the comparative experiments (the main project of the course).</p>
        <p>When the students finalised the experimental design and improved the iStar models,
they conducted the experimental tasks. Finally, they collected data, performed data
analysis, and reported the results via a scientific paper, a poster, and an elevator pitch.
3</p>
        <p>Using iStar 2.0: the ARM course projects
During the ARM course, the students conducted a design science project with a basic
design cycle and a full empirical cycle. For this, the students were distributed in teams
of 3-4 people; each team elected a team leader (see Fig. 2). Since it was not the objective
of the course to build information systems artefact from scratch, the students studied
existent iStar 2.0 artefacts in the context of a design science project.</p>
        <p>For the design cycle, each team selected 1 out of 4 iStar 2.0 artefacts. For this year,
we have selected two artefacts that prescribe guidelines and techniques that use iStar
2.0 models (A1 and A2), and two artefacts that support the specification and syntactical
notation of iStar 2.0 models (A3 and A4).</p>
        <p>For the empirical cycle, each team conducted a comparative experiment for an iStar
2.0 artefact. During the empirical cycle, students analysed a given a problem with the
artefact, designed an experiment, analysed the threats on the validity of the experiment,
executed the experimental tasks, and analysed the experimental results. For the
experimental tasks, the students acted as researchers of their own experiment, also as
experimental subjects of the experiments of their researcher fellows. For example, in the case
of the team A1.1, they took the role of researchers for the artefact P1 whereas they were
the experimental subjects of the teams A2.1, A3.1, and A4.1 (see Fig. 2).
A1
SUBJECTS
Teams:
A3.2
A3.3
A3.4
DATA A1</p>
        <p>A3
SUBJECTS
Teams:
A4.2
A4.3
A4.4</p>
        <p>DATA A3
TEAM A1.1 TEAM A1.2 TEAM A1.3 TEAM A1.4 TEAM A1.5 TEAM A2.1 TEAM A2.2 TEAM A2.3 TEAM A2.4 TEAM A2.5
SUBJECTS
Teams:
A2.1
A2.2
A2.3</p>
        <p>SUBJECTS
Teams:
A2.4
A2.5
A3.1</p>
        <p>SUBJECTS SUBJECTS
Teams: Teams:
A3.5 A4.3
A4.1 A4.4
A4.2 A4.5</p>
        <p>SUBJECTS
Teams:
A1.1
A1.2
A1.3</p>
        <p>SUBJECTS
Teams:
A1.4
A1.5
A3.1
SUBJECTS
Teams:
A1.1
A1.2
A1.3</p>
        <p>SUBJECTS
Teams:
A1.4
A1.5</p>
        <p>A4.1
Legend
PROJECT SUBJECTS MEMBER LTEEAADMER ASSOCIATION</p>
        <p>TEAM/
TEAM A3.1 TEAM A3.2 TEAM A3.3 TEAM A3.4 TEAM A3.5 TEAM A4.1 TEAM A4.2 TEAM A4.3 TEAM A4.4 TEAM A4.5
SUBJECTS SUBJECTS SUBJECTS
Teams: Teams: Teams:
A4.5 A2.3 A1.1
A2.1 A2.4 A1.2
A2.2 A2.5 A1.3</p>
        <p>SUBJECTS
Teams:
A1.4
A1.5
A2.1</p>
        <p>A2
SUBJECTS
Teams:
A3.2
A3.3
A3.4
DATA A2</p>
        <p>A4
SUBJECTS
Teams:
A2.2
A2.3
A2.4
DATA A4</p>
        <p>SUBJECTS
Teams:
A3.5
A4.1
A4.2</p>
        <p>SUBJECTS
Teams:
A4.3
A4.4</p>
        <p>A4.5
SUBJECTS
Teams:
A2.5
A3.1
A3.2</p>
        <p>
          SUBJECTS
Teams:
A3.3
A3.4
A3.5
For the design of the comparative experiments, the students applied the experimental
protocol for experimentation in software engineering prescribed by Wohlin et al. [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ].
3.1
        </p>
        <p>Experimental objects: iStar 2.0 artefacts
We provided the students with iStar 2.0 artefacts for their evaluation. Table 2 presents
a summary of the artefacts2.
2 Further details about the given artefacts are available as part of the course material:</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>A2: Delta</title>
    </sec>
    <sec id="sec-6">
      <title>Analysis technique [13]</title>
    </sec>
    <sec id="sec-7">
      <title>A3: piStar tool</title>
      <p>
        [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]
A4: iStar 2.0
notation and
      </p>
    </sec>
    <sec id="sec-8">
      <title>Moody’s visual notation [15] [16]</title>
    </sec>
    <sec id="sec-9">
      <title>Description: Delta Analysis is a technique for the analysis of differences</title>
      <p>and information gathering of two information systems. The Delta Analysis
technique serves on the purpose to analyse the delta of two information
systems. Delta Analysis is model-based; thus, the comparison or delta is
performed between pair of models that specify information systems. The</p>
    </sec>
    <sec id="sec-10">
      <title>Delta Analysis technique is general enough to be applied to any pair of conceptual models (e.g., specification of information system goals, business process, interaction requirements, etc.).</title>
    </sec>
    <sec id="sec-11">
      <title>Objective: Conduct a comparative experiment in order to evaluate the benefits and drawbacks of using the Delta Analysis technique in terms of performance and perceptions from a practitioner point of view when comparing iStar models.</title>
    </sec>
    <sec id="sec-12">
      <title>Description: Just like other modelling languages, iStar 2.0 modellers often</title>
      <p>make errors and create models that are not compliant with the syntax. To
such extent, iStar 2.0 comes with meta-model enriched with additional
constraints about syntactic well formedness. iStar 2.0 models can be drawn by
hand on paper, digitally using a general purpose drawing tool such as
Microsoft Visio, or using a dedicated application for iStar 2.0 such as piStar.</p>
    </sec>
    <sec id="sec-13">
      <title>Objective: Conduct a comparative experiment in order to evaluate the impact of using piStar in terms of performance and perceptions from a practitioner point of view.</title>
    </sec>
    <sec id="sec-14">
      <title>Description: The standard iStar 2.0 notation uses standard shapes (from</title>
      <p>the original version of iStar) to represent concepts. For example, circles
represent actors, stadium shaped nodes represent goals, and hexagons
represent tasks. The relationships between these constructs are captured by
links between those shapes, sometimes labelled by text. The arrow heads
used to connect the directed edges may differ for different relationships.</p>
    </sec>
    <sec id="sec-15">
      <title>Moody et al. discuss the advantages and disadvantages of the standard iStar notation and suggest improvements on the visual notation of iStar, basing these suggestions on theory of visual design.</title>
    </sec>
    <sec id="sec-16">
      <title>Objective: Conduct a comparative experiment in order to evaluate the benefits of using the Moody’s notation for iStar 2.0 models in terms of performance and perceptions from a practitioner point of view</title>
      <p>To illustrate the experimental setups used in the course, we describe the project of the
students that have selected the artefact A4. In this project, the students (5 teams) have
designed a comparative expeiment where the standard iStar2.0 notation is compared
against the Moody’s visual notation in terms of practioners‘ performance and
perceptions (see Fig. 3). Each team had between 9 to 11 experimental subjects. For this
experiment, we defined dependent and independent variables, which were measured by
means of two experimental tasks in two weeks (see Fig. 3, week 1 and week 2). Each
team of artefact A4 elected one context and specified models using the standard iStar
2.0 and Moody’s notations. In the first experimental task the experimental subjects were
divided in two groups: the group A analysed a goal model specified by means of the
iStar 2.0 notation, and the group B analysed a goal model based on Moody’s notation.
In the second experimental task, each team chose a different context from the one used
for the experimental task 1 and defined the iStar 2.0 and Moody‘s models. In week 2,
the teams switched the experimental subjects as described in Fig. 3; and kept the same
complexity of the experimental objects in terms of the amount of modelling elements
and type of elements that were used in the models for the experimental task 1.
TREATMENT</p>
      <p>INPUT
MODEL</p>
      <p>COMPRENHENSIBILITY
READABILITY</p>
      <p>USEFULNESS
EFFICIENCY</p>
      <p>EASE OF USE
INDEPENDENT VARIABLES</p>
      <p>PERFORMANCE</p>
      <p>PERCEPTIONS
DEPENDENT VARIABLES</p>
      <p>INTENTION
TO USE</p>
      <sec id="sec-16-1">
        <title>Weeks Experimental task Subjects</title>
        <p>Week 1 1 iStar 2.0 A</p>
      </sec>
    </sec>
    <sec id="sec-17">
      <title>Moody B</title>
      <p>Week 2 2 iStar 2.0 B</p>
    </sec>
    <sec id="sec-18">
      <title>Moody A</title>
      <p>
        To measure comprehensibility and readability, the teams have designed questionnaires
with context dependent questions about the iStar 2.0 and Moody’s models. In this case,
10 questions were dedicated to readability and 5 to comprehensibility. For the
efficiency, each team registered the amount of time that each subject took to finish the
questionnaire. Finally, the teams measured usefulness, ease of use and intention to use
according to a quality framework [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ].
4
      </p>
      <p>Discussion and lessons learnt
In this paper, we reported our experience in using conceptual modelling as artefact for
teaching non-conventional information systems courses like research methods. A key
aim of our attempt is to make students understand that conceptual modelling research
goes well beyond reading and creating models, but rather involves thorough theoretical
and empirical studies concerning conceptual modelling artefacts.</p>
      <p>In our case, we describe the design of the Advanced Research Methods course (ARM),
which has as a main component the Design Science Method. As part of the main project
of the course, students conducted a design science project in order to evaluate artefacts
in context. For the academic year 2016-2017, students evaluated conceptual model
artefacts by means of a comparative experiment, wrote a research paper, and presented
the results by means of a poster and elevator pitch. As a proof of concept, the students
evaluated iStar 2.0 artefacts.</p>
      <p>Reflecting on the intended learning outcomes and our experience, we highlight the
following positive findings and opportunities for improvement.
4.1</p>
      <p>Positive findings
 The existence of conceptual modelling language variants can be beneficial! One of
the main criticisms made to the conceptual modelling community is that many
variants of a given language (and related artefacts) are proposed. However, this
drawback turned into an advantage for the ARM course, for we could easily select
different iStar 2.0 artefacts to evaluate. Other conceptual modelling languages, such as for
business processes, offer a comparable artefact selection space to be exploited.
 Easily customizable materials and artefacts. Conceptual modelling artefacts are
adaptable for classroom settings without investing considerable resources. It is
relatively simple and nonintrusive to modify the graphical notation, alter the syntax, or
build a new analysis algorithm. Compare this to the effort required to modify a
software product (e.g., user interface, algorithm, input devices). Thus, conceptual
models are excellent artefacts for use in a research methods course.
 Experimental outcomes trigger new design cycles for conceptual model artefacts.</p>
      <p>The students gained first-hand experience about the limitations of existing
conceptual modeling artifacts. This is a much more powerful learning experience compared
to a teacher telling them that a modelling language suffers from a certain problem.
We are confident that the obtained findings will lead some students to follow a new
design cycle during their master’s thesis.
 Comparable complexity of the experiments. Despite the differences of the four
evaluated artefacts, it was possible for the instructor to keep a balance in workload of
each team in terms of artefacts to build and variables to measure. For example, the
teams measured subject performance and perceptions for each artefact, which
required them to build experimental objects (iStar 2.0 models plus other objects
according to the type of artefact, like Moody’s models), create questionnaires to
evaluate subjects’ perceptions, and record the time spent per subject during the execution
of the experimental task. The balance in the design and workload of the projects was
a key point to avoid frustration and competition among the teams.
4.2</p>
      <p>Opportunities for improvement
 Managing multiple experiments at the same time. It was difficult to assist four
different research projects and schedule the parallel execution of 40 experimental task
(20 teams, two experimental tasks each) in two weeks. These aspects need to be
readjusted by, e.g., offering only a couple projects and fewer experimental objects.
 Testing the achievement of the iStar ILOs. Although we supported students by giving
them feedback about their models until they reached a solid version, we did not
evaluated the actual knowledge in iStar modelling. For the next edition of the ARM
course, it is necessary to evaluate the extent to which each student achieved the
iStarrelated ILOs; this will reduce the threats to validity of the experiments given the
analysis of iStar models that was required for all the experimental tasks.
 On the difficulty of establishing scientific rigor. Students learnt how to identify
threats to the validity of the experiments, but we did not have sufficient time or
experience to avoid many of them. Some threats were related to the difficulty to
manage four experiments and to ensure the participation of the students in the
experimental tasks. We noticed that the students tend to feel frustrated if they need to
confront a threat to the validity of their experiments. It is important to allocate sufficient
time for the students to prevent the most important threats and to teach them how to
mitigate the threats when they occur. For example, testing the subjects’ knowledge
of iStar would help ensure an appropriate execution of the experimental tasks.
Looking at the intended learning objectives for ARM, we find that the experimental
setting and the employment of iStar 2.0 are appropriate for a master-level course,
especially thanks to the existence of many artefacts and the possibility to follow a full
experimental protocol. In the upcoming years, we plan to improve the course design by
establishing a better distribution of teams and less artefacts to evaluate. Also, we plan
to reduce the amount of experimental objects (one per artefact, but not one per team),
and to help the students manage the threats to the validity of the experimental results.
5</p>
    </sec>
  </body>
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