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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>The Impact of Gamification on Socio-technical Communities: A Case for Network Analysis</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Antti Knutas</string-name>
          <email>antti.knutas@dcu.ie</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Timo Hynninen</string-name>
          <email>timo.hynninen@lut</email>
          <email>timo.hynninen@lut.fi</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Lappeenranta University of Technology</institution>
          ,
          <addr-line>Lappeenranta</addr-line>
          ,
          <country country="FI">Finland</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Lero, the Irish Software Research Centre</institution>
          ,
          <addr-line>Dublin</addr-line>
          ,
          <country country="IE">Ireland</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Designing for motivating and engaging experiences is at the core of gamification. The results of gamification are often evaluated with user experience testing involving recordings, surveys, and interviews. However, in multi-user socio-technical environments the benefits of gamification are often realized in interactions between users. We propose that social network analysis should be used more to analyze the impact of gamification at community level. To demonstrate the approach, we present a study where a gamified computer-supported collaborative learning system was introduced to a course, and compare the course to a previous instance. Furthermore, we present several examples of how social network analysis can be used with hypothesis testing and discuss the benefits of the approach.</p>
      </abstract>
      <kwd-group>
        <kwd>Author Keywords gamification</kwd>
        <kwd>social network analysis</kwd>
        <kwd>hypothesis testing</kwd>
        <kwd>computer-supported collaborative learning</kwd>
        <kwd>socio-technical systems</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        INTRODUCTION
Collaborative learning is a learning method where students
have a symmetry of action, knowledge and status, and have
a low division of labor [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. Computer-supported
collaborative learning (CSCL) facilitates the interaction with software
tools and increases potential for creative activities and social
interaction [
        <xref ref-type="bibr" rid="ref30">30</xref>
        ]. Collaborative learning is a commonly used
method in software engineering education as it prepares
students to work in software teams as independent experts. In
recent studies, it has been shown that students can be guided
towards educational goals like collaboration by using
gamification [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ], which is the application of game-like elements to
non-game environments [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>GHItaly18: 2nd Workshop on Games-Human Interaction, May 29th, 2018, Castiglione
della Pescaia, Grosseto (Italy).</p>
      <p>Copyright © 2018 for the individual papers by the papers’ authors. Copying permitted
for private and academic purposes. This volume is published and copyrighted by its
editors.</p>
      <p>
        The gamification of learning in software engineering
education has been studied earlier [
        <xref ref-type="bibr" rid="ref14 ref25 ref3">25, 14, 3</xref>
        ], mostly at the level of
individual students. However, software engineering education
classes and software engineering are communities, or
sociotechnical entities [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ], which are interconnected by personal
and technical communication channels. In this context, we
define a socio-technical system as a complex system which
involves both physical–technical elements and networks of
interdependent actors [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. These technological structures are
not only neutral instruments, but also shape users’ perceptions,
behavioural patterns, and activities [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. Computer-supported
collaborative learning tools as software systems always
include certain inbuilt assumptions, interaction methods, and
rules. An issue tracker such as GitHub enables collaboration
in a different way than for example a forum software. When
gamification is added into the mix, it adds explicit interaction
rules. Embedding a technical element into the social
environment changes not only the experience of an individual users,
but has the potential to impact interaction patterns and rules
of social interaction.
      </p>
      <p>
        We propose that social network analysis (SNA) is a fitting
research approach for investigating the impact of new
technologies in socio-technical systems, such as in the case of applying
gamification. Social network analysis can be summarized to
be an interdisciplinary research field about who communicates
with whom, in which social relationships are viewed in terms
of the network theory [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ]. In social network analysis,
communication between individual or social units are mapped into
a communication matrix and then modeled as graphs that are
composed of nodes and edges. Nodes represent individuals
and edges the connections or communications between them.
These graphs can be used to visualize communication patterns
in socio-technical systems systems. Additionally, in the graph
theory there are different mathematical tools available, which
can be used for example to estimate the relative influence of
nodes in the graph or analyze the graph by the connection
patterns of the nodes [
        <xref ref-type="bibr" rid="ref2 ref29 ref4">2, 4, 29</xref>
        ].
      </p>
      <p>Currently many social network analysis -based studies rely
only on descriptive statistics and omit hypothesis formulation
and evaluation. We make a case that hypothesis testing is
an essential part of empirical studies that use quantitative
methods, such as SNA. Wohlin et al. [32, p. 12] summarize
the the importance of hypothesis testing for generating new
knowledge as follows. "In science, physical phenomena are
addressed by putting forward hypotheses. The phenomenon is
observed and if the observations are in line with the hypothesis,
this becomes evidence for the hypothesis. Experiments are
important to test the hypothesis and in particular the predictive
ability of the hypothesis. If the new experiments support
the hypothesis, then we have more evidence in favor of the
hypothesis." If the study remains at the level of descriptive
statistics, no evidence is created to support the presented new
knowledge. 1
To illustrate the social network analysis as a research method
and how it can be used in hypothesis testing, we present a study
of how embedding technical elements into a collaborative
learning course creates a new socio-technical system. The
goal is to evaluate how the new elements affect the structure of
collaboration in and between student teams. First, we present
descriptive statistics generated by social network analysis and
then test several hypotheses about the impact based on that
data. We conclude the paper with discussion of the study
results and what kind of insight social network analysis can
provide for other studies.</p>
      <p>
        RELATED WORK ON ANALYSIS OF GAMIFIED
COMMUNITIES
Social network analysis has been utilized by social scientists
to explain different phenomena. Borgatti et al. [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] divide
the various themes that can be examined by SNA into the
similarities of actors, their social relations, interactions and
flows (transferring physical or intellectual property between
actors).
      </p>
      <p>
        A number of authors have previously conducted research in
group and peer learning activities in software engineering
education using social network analysis [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]. This is because
the effects of social networking in an educational setting can
have a substantial impact on learning performance [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. For
example, the study by De Laat et al. [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ] presents an overview
of how social network analysis can be applied in the field
of CSCL. The authors build a case for utilizing SNA to
investigate the group dynamics in a CSCL environment. The
study emphasizes that in order to fully understand student
participation in CSCL environments, we must analyze who are
the actors in the collaborative learning task, and if actors are
participating actively or peripherally. It is also important to
understand how the different methods of participation change
over time.
      </p>
      <p>
        In terms of social network analysis in gamified CSCL context,
de-Marcos et al. [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] used SNA to investigate a gamified
elearning course. In the study different network metrics were
assessed in how well they can predict academic performance.
The investigation found potential in the use of network metrics
to predict learning achievement but also found limitations to
their applicability beyond central nodes in the social network.
This study is one of the few studies which have evaluated the
impact of gamification on socio-technical communities from a
network analysis perspective.
      </p>
      <p>1The authors acknowledge that this is a very positivist view
and other philosophies of science or qualitative approaches are just
as valid. However, in positivist-quantitative approaches hypothesis
testing is essential.</p>
      <p>
        More recently SNA has been utilized by Wise &amp; Cui [
        <xref ref-type="bibr" rid="ref31">31</xref>
        ],
for example, to distinguish social relationships in MOOC
discussion forums. Their study showed connections between
network structure and discussion practices. The study also
pointed out that interactions involving course content related
discussion and other discussion should be examined
separately.
      </p>
      <p>SOCIAL</p>
      <p>NETWORK</p>
      <p>ANALYSIS</p>
      <p>AS</p>
      <p>A</p>
      <p>
        RESEARCH
METHOD
Social network analysis is based on graph theory, which is
a concept related to mathematics and information sciences
[
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. Central concepts in graph theory are network, node, and
edge. A network is composed of actors, or nodes, between
which are connections, or edges. A common method in social
network analysis is to store graphs as adjacency matrices.
From these matrices one can calculate different statistics and
characteristics with graph theory and matrix algebra. Several
applications have been developed to automate the analysis,
such as UCINET [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] and Gephi [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. A common method to
visualize the graph matrix is a sociogram, which is is a visual
representation of the nodes and and their edges. Most often
the nodes are represented as circles and edges as connecting
lines.
      </p>
      <p>Descriptive Statistics for Graphs and Nodes
The degree is most essential of node characteristics. The node
degree indicates the number of edges connected to a node, or
the number of connections the node has to other nodes. The
weighted degree also takes into account the different values the
edges might have. Additionally, the most simple measure of
centrality, the degree centrality, is derived from node degrees.
Degree centrality is calculated from the sum of edges a node
has.</p>
      <p>Graph density is derived from node degrees. It is a value
between zero and one, and it indicates how many connections
have been established of all possible connections. If all nodes
are connected to all other nodes, it is 1. If the graph has no
edges, then network density is 0.</p>
      <p>
        A social network can be composed of one or several
components. A component is an element of a social network where a
path can be traced from one node to another. The number of
connected components can be evaluated how fragmented the
network is. In well-functioning socio-technical systems the
desired number of connected components is just one.
Centrality is a method to measure nodes’ relative importance
in a graph [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ]. Application areas for centrality include finding
influencers in social media or finding the most active
collaborators in learning. Degree centrality is the easiest to calculate
and was covered earlier in this section. Betweenness centrality
is the measure of all the shortest paths that go through the node.
Other, more advanced methods such as eigenvector centrality
are beyond the scope of this article.
      </p>
      <p>
        Regression Analysis and Comparisons in Social Network
Analysis
Traditional hypothesis testing, such as regression analysis, is
difficult to use on networks, because edges exist as dyads
between two nodes. The Multiple Regression Quadratic
Assignment Procedure (MRQAP) method was developed to
address this issue and it allows analyzing the effect of external
variables on network structure [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. Correlation between
networks can be analyzed with a related method, the Quadratic
Assignment Procedure (QAP) [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ].
      </p>
      <p>
        CASE STUDY: ANALYZING THE IMPACT OF
GAMIFICATION ON STUDENT COLLABORATION
In this section, we present a case study where we perform
comparative social network analysis of two subsequent
teamworkbased computer-supported collaborative courses in software
engineering at master’s level. The research data has been
collected in earlier studies [
        <xref ref-type="bibr" rid="ref19 ref20">19, 20</xref>
        ]. The two courses were
arranged in subsequent years with the main difference being
that in the second year a gamified, computer-supported
collaboration platform was introduced to the course. In this paper,
we take the analysis further with hypothesis testing, with an
emphasis on evaluating the impact of the artifact introduced
in the second study.
      </p>
      <p>
        In the first study [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ], we observed 17 students over a five day
long intensive format and collaborative software engineering
course, arranged in the Code Camp format [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ]. The course
had 10 hours of lecturing and 40 to 64 hours (depending on
the student team) of collaborative teamwork around a set task.
The topic for the course was to develop a new mobile or tablet
application before the deadline on the fifth day. The teams
were free to choose their own path to a solution within the
theme and how to achieve it. The students had no other courses
during the week. The students spent their time in the same
shared computer classroom, with each student team sitting at
their own table group. After the kickoff event and a technology
tutorial, the teachers were available to advise when requested
during the rest of the week and to facilitate inter-team
collaboration. Most of the course participants were master’s
level students with previous experience of other programming
projects. All recorded collaborative communications occurred
offline in the classroom in this study.
      </p>
      <p>
        All student interactions that occurred in the classroom were
recorded during the first study. The video and audio recordings
were combined into multi-angle and surround sound videos
that allowed the researchers reviewing the video to analyze
several concurrent interactions. This resulted in 40 hours of
video, from which 3366 interactions were coded for analysis.
The data analysis presented in this paper is sourced from the
quantitative analysis results of the video recordings.
The second study [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ], with the computer-supported
collaborative learning system, was similar to the first one and also
arranged in the Code Camp format [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ]. The only differences
were the introduction of the computer-supported
collaborative learning system, the theme of the course, and the number
of participants. This time there were 22 participants divided
into six teams. The topic of the course was using open data
for sustainability. In this study, all recorded collaborative
communications occurred online in the computer-supported
collaboration system. The data analysis presented in this paper
was sourced from the system log files.
      </p>
      <p>
        Software Artifact
The software artifact for computer-supported collaboration in
software engineering student teamwork, originally presented
in [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ], was created following along the following principles:
Increased team collaboration, extended collaborative
communication between students, and explicit goal communication
that supports shared goal setting and goal achievement.
These tenets were realized as a collaboration platform that
concentrated around setting team goals and issues, viewing
the status of other teams and using a chat-based tool, Slack,
to communicate and share information regarding the goals
and issues. The information and views concentrated around
three main views, with a sidebar and notifications showing
additional information when needed. The guidelines of
responsive design were followed in the implementation of the
views, with the system working equally well on desktops or
mobile phones. The selected chat system also had a mobile
client application for iOS and Android, enabling continuous
collaborative communication for the community.
      </p>
      <p>
        Social Network Analysis Results
We performed descriptive social network analysis with the
Gephi software [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and hypothesis testing with the R statistical
programming language [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ]. First, we produced descriptive
statistics for the two networks for comparison purposes, such
as the number of components in the network, various
indicators for network size, and the average degree for the nodes.
Then we tested hypotheses of whether the distribution of node
attributes, such as degree and centrality, were different in the
networks, and how well being in the same group predicts two
students having a collaborative connection.
      </p>
      <p>
        Descriptive Statistics
We analyzed the social networks of two studies, classroom and
online communication, and produced descriptive statistics of
the networks as presented in Table 1. The online system had a
little more nodes and a lot more recorded interactions. Both
networks had only one connected component, which means
that there was a path from each node to any other node. The
online network was a little less connected, which is signified
by an increased network diameter and lower network density.
Despite the lower network density, on average a node had more
connections to other nodes in the online network as signified by
the average degree. However, the average weighed degree was
much higher in the classroom, implying that students in the
online system were slightly better connected and
classroombased students established stronger and more even ties.
Hypothesis testing
Descriptive statistics are not enough to evaluate proof of
evidence when for example making claims about the differences
in social networks. For this, we need statistical hypothesis
testing which can give us the probability of the evidence
supporting our hypothesis being significant, and the effect size of
the evidence [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. An obtained p-value represents the
probability of observing the current data due to chance when the null
hypothesis is true. Effect size allows us to evaluate how
substantial the evaluated phenomenon is, after it has been shown
that the phenomenon probably exists.
We first used the Mann–Whitney U test [
        <xref ref-type="bibr" rid="ref32">32</xref>
        ] to test the
difference in distributions between the datasets because of its
suitability for non-normal data. A continuity correction was
enabled to compensate for non-continuous variables [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. The
Bonferroni correction was used to adjust the p-value to
compensate for the family-wise error rate in multiple comparisons
[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. We calculated effect size r using guidelines by Fritz et
al. [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] for the Mann-Whitney U test. We evaluate the effect
size as proposed by Cohen [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] that in r a large effect is .5, a
medium effect is .3, and a small effect is .1.
      </p>
      <p>Our null hypotheses is that there is no difference in the
distributions of node degrees or betweenness centralities between the
networks. Node degree and two node centrality variables were
tested to establish differences in the distribution of connections
and whether there was overall differences in how the relative
importance of nodes were distributed. The Mann-Whitney U
test results are summarized in Table 2, with the sum of ranks
denoted by the U-value, the probability by the p-value, and
effect size by r. When evaluating node degrees and betweenness
centrality we fail to reject the null hypothesis, with there being
no statistically significant difference between the networks
in these aspects. When evaluating weighted degrees we can
reject the null hypothesis and accept an alternative
hypothesis that there is a difference in distributions between the two
networks in this aspect.</p>
      <p>
        Finally, we want to evaluate the impact of external factors
on the network. For this purpose we use MRQAP to apply
regression analysis to evaluate the effect of external variables
on dyads, or the connections between nodes. For the MRQAP
analysis we used the R sna library [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] and its network multiple
regression function.
      </p>
      <p>
        In our first regression analysis we evaluate whether being in the
same team predicts a connection in the classroom. The
regression model using MRQAP and ordinal least squares regression
statistically significantly predicts collaborative connections, F
(1, 304) = 38.38, p &lt; .001, adj. R2 = .11. Regression
coefficient estimate of 0.41 on the same team variable means that
being in the same team increases the possibility of a
connection by 41%. Cohen’s f2 for effect size is 0.13, which means a
medium effect [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
      </p>
      <p>
        In the second regression analysis we evaluate whether being
in the same team predicts a connection in the online
platform. The regression model using MRQAP and ordinal least
squares regression statistically significantly predicts
collaborative connections, F (1, 504) = 72.28, p &lt; .001, adj. R2
= .12. Regression coefficient estimate of 0.56 on the same
team variable means that being in the same team increases the
possibility of a connection by 56%. Cohen’s f2 for effect size
is 0.14 which means a medium effect [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
      </p>
      <p>Despite the medium effect size and statistical significance,
in both cases the R2 value is low. The same-team variable
predicts only 11 to 12% of the variance, which means that a
social connection is mainly predicted by other factors.
Discussing the Analysis Results
When evaluating the differences in the networks, we made
the following findings: The online network from the second
study was slightly larger than the classroom collaboration
network in the first study. The online network had vastly more
interactions, but the nodes had stronger ties in the classroom
network in a statistically significant manner. In both networks,
there was the same distribution of betweenness centralities,
which means there were the same distribution of central nodes
mediating communication. According to the MRQAP results,
being in the same team was a stronger predictor for
collaboration in the online network, which means that the classroom
network had stronger inter-team collaboration. A summary of
the tested hypotheses and outcomes are presented in Table 3.
At a first look the gamified online communication platform
appears to increase collaborative communication between
students. The three essential goals of the platform were to
increase communication, enable stronger inter-team
communication, and to reduce the hierarchy in communication. However,
after testing our hypotheses with social network analysis data,
we found that compared to plain classroom communication,
the online platform failed to enable stronger social ties,
increased inter-team communication, or more diverse patterns of
collaboration. As the CSCL platform had an increased number
of interactions, these outcomes might not have been
discovered without in-depth social network analysis and statistical
evaluation.</p>
      <p>These discoveries were enabled by statistical hypothesis
testing, which allowed us to evaluate the strength of the evidence
in regard to statistical significance and effect size. For
example, the beneficial differences in betweenness centralities
might seem plausible when presented side by side as
descriptive statistics. However, by statistically testing our hypotheses,
we were able to conclude that the difference is not significant
and the effect size was trivial.</p>
      <p>DISCUSSION AND CONCLUSION
In this paper, we demonstrated how social network analysis
can be used in hypothesis testing -based evaluation of
sociotechnical communities. In the demonstration we evaluated
the impact of a new software artifact. The artifact at a glance
appeared to increase communication between participants of
the community, but when evaluating social ties, the artifact’s
impact was more complex than reflected by simple usage
statistics, and not fully beneficial.</p>
    </sec>
    <sec id="sec-2">
      <title>Variable</title>
      <sec id="sec-2-1">
        <title>Degree</title>
      </sec>
      <sec id="sec-2-2">
        <title>Being in the same team is a statistically significant predictor for the strength of connection between the nodes.</title>
        <p>
          Social network analysis is a research method worth
considering when studying the impact of technological artifacts on
socio-technical communities, such as gamified systems. It
is a powerful technique, especially when combined with
hypothesis testing. It can reveal patterns of actions in complex,
interlinked systems that involve multiple interdependent
actors. The number of these socio-technical systems will only
increase with the ongoing digital transformation in our society.
Some studies already use social network analysis to evaluate
the impact of gamification on the educational communities,
such as the line of research by de-Marcos et al. [
          <xref ref-type="bibr" rid="ref11 ref12">11, 12</xref>
          ].
However, in gamification, computer-supported collaboration,
and socio-technical research this is still in the minority [
          <xref ref-type="bibr" rid="ref14 ref21 ref25 ref3">3, 14,
21, 25</xref>
          ]. Additionally, many social network analysis studies do
not use hypothesis testing or regression analysis and rely just
on descriptive statistics. We recommend publishing tutorials,
reviews, and methodological demonstrations of the benefits
of more in-depth and rigorous research approaches in social
network analysis. Social network analysis has potential as a
research method in the field of gamification and beyond. As
future work, aspects of social network analysis not covered by
this paper, such as community detection and more advanced
approaches to centrality, should be demonstrated in regard to
compatibility with hypothesis testing.
        </p>
        <p>ACKNOWLEDGMENTS
The work of the first author was supported by the Ulla
Tuominen Foundation. This study was partially funded by the
European Union Regional Development Fund grant number
A70554, “Kyberturvallisuusosaamisen ja liiketoiminnan
kehittäminen”, administrated by the council of Kymenlaakso. This
work was supported, in part, by Science Foundation Ireland
grant 13/RC/2094 and co-funded under the European Regional
Development Fund through the Southern &amp; Eastern Regional
Operational Programme to Lero - the Irish Software Research
Centre (www.lero.ie).
p-value
0.37
0.97</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Outcomes</title>
      <sec id="sec-3-1">
        <title>Node degrees and betweenness centralities have no</title>
        <p>significant differences. Weighed degrees have.
Statistically significant relationship exists between the
variables. In the online case the relationship is somewhat
stronger.</p>
      </sec>
    </sec>
  </body>
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