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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Trying to Increase the Mature Use of Agile Practices by Group Development Psychology Training - An Experiment</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Lucas Gren Chalmers and the University of Gothenburg Gothenburg, Sweden 412-92 and University of Sa ̃o Paulo Sa ̃o Paulo</institution>
          ,
          <addr-line>Brazil 05508-090</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2016</year>
      </pub-date>
      <fpage>50</fpage>
      <lpage>57</lpage>
      <abstract>
        <p>-There has been some evidence that agility is connected to the group maturity of software development teams. This study aims at conducting group development psychology training with student teams, participating in a project course at university, and compare their group effectiveness score to their agility usage over time in a longitudinal design. Seven XP student teams were measured twice (43+40), which means 83 data points divided into two groups (an experimental group and one control group). The results showed that the agility measurement was not possible to increase by giving a 1.5-hour of group psychology lecture and discussion over a two-month period. The non-significant result was probably due to the fact that 1.5 hours of training were not enough to change the work methods of these student teams, or, a causal relationship does not exist between the two concepts. A third option could be that the experiential setting of real teams, even at a university, has many more variables not taken into account in this experiment that affect the two concepts. We therefore have no conclusions to draw based on the expected effects. However, we believe these concepts have to be connected since agile software development is based on teamwork to a large extent, but there are probable many more confounding or mediating factors.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>
        Agile Project Management and its methods evolved during
the nineties on ideas from lean production and more flexible
product development [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], but also from practical experience
saving IT projects that were about to fail [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The main
difference between lean production and agile project management
is that both management ideas admit they do not know what
the best end-product would look like far in advance [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. The
agile development processes are often intimately connected
to high performing, self-managing and mature teams [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and
the way group norms are set has been shown to increase
performance [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Agile development, as compared to
plandriven ditto, implies more communication and focus on human
factors, which make the group psychology aspects of teams
a key ingredient [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. However, the agile processes do not
explicitly include the temporal perspective of what happens
to all teams over time from a group maturity perspective.
      </p>
      <p>In this experiment, we conducted a longitudinal study of
seven agile teams to see if the group development affects
process agility. By giving half of the teams training in group
psychology theory we hoped to see an effect on their measured
agility. However, by only giving a 1.5-hour lecture, we did not
see such an effect. We instead discuss reasons for our
nonsignificant results and suggest next steps for future attempts at
finding such effects in complex social systems.</p>
      <p>
        We follow Jedlitschka, Ciolkowski and Pfahl’s [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]
guidelines on how to to report experiments on software engineering
throughout this paper. We will therefore start by giving a
theoretical background (Section II), describe the experiment
in detail (Section III), analyze the data and show descriptive
statistics and tests (Section IV), and, finally, discuss the result
(Section V) and provide conclusions and suggestions for future
work (Section VI).
      </p>
      <sec id="sec-1-1">
        <title>A. Context</title>
        <p>
          When software development teams transition to an agile
approach (i.e. more team-based work) more of the process
is dependent on how well the team cooperates [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]. The agile
adoption sometimes fails due to the fact that an agile transition
is a cultural change as well, which impose new constellations
of teams [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. To further explore the causal relationship
between the group dynamics and agile practices over time,
would therefore be interesting, both from a research and an
industrial perspective, in order to guide agile adoptions better.
        </p>
      </sec>
      <sec id="sec-1-2">
        <title>B. Problem statement</title>
        <p>
          Many aspects of group dynamics come into play in the
team-based workplace [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ]. There are studies showing a
correlation between group maturity and agile concepts (see
e.g. [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ]), however, little is known of any causal relationship
between them. Correlation analysis only show the connection
between the two. If the mature usage of agile practices are
directly dependent on group development aspects has not yet
been investigated. Therefore, it would be interesting to see
if group psychology training of agile software development
teams could increase the adoption of concrete agile practices.
        </p>
        <p>BACKGROUND</p>
      </sec>
      <sec id="sec-1-3">
        <title>A. Agile methods (processes)</title>
        <p>Agile methodologies can be seen as an approach rather
than a technique that mostly change the culture and values
behind managing projects. There are some more concrete agile
methods, but they all basically share the same values. However,
in order to understand how these methods work in practice, we
will now shortly present some of the agile practices and how
the values are implemented.</p>
        <p>
          a) eXtreme programming (XP): eXtreme programming
was the first method created by the agile community and is
the most researched method [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] and is considered relatively
strict and controlled. The practices that implement the agile
principles are [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ]:
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
        </p>
        <p>The planning game. In the beginning of each
iteration, the team, managers, and customers meet and
write requirements in form of user stories (written in
clear natural language and in a way that everybody
can understand). During these meetings the whole
group estimates and prioritizes the requirements.</p>
        <p>Small releases. Working software is up and running
and delivered very fast and new versions are released
continuously, from every few days to every few
weeks.</p>
        <p>Metaphor. Customers, managers, and developers
model the system after a constructed metaphor or set
of metaphors.</p>
        <p>Simple design. Developers are asked to keep design
as simple as possible.</p>
        <p>Tests. The development is test-driven (TDD), i.e., the
test are written before the code.</p>
        <p>Re-factoring. The code should be revised and
simplified over time.</p>
        <p>Pair-programming. All code is written by having two
developers per machine.</p>
        <p>Continuous integration. The developers integrate new
code into the system as often as possible. However, all
code must pass the testing otherwise it is discarded.
Collective ownership. Developers can change code
wherever necessary and the overall code is assessed.
On-site customer. A customer is in the team all the
time to answer questions so the team always works
according to what is needed.
40-hour work week. The team works with a
sustainable pace defined as a 40 hour work week. The
requirement selected for each iteration should never
mean that the team needs to work overtime.</p>
        <p>Open workspace. The team should be collocated and
fit in the same room. The layout of the room should
make cooperation and communication easy.</p>
        <p>b) Scrum: Scrum is based on XP and is one of the
more common methodologies and is built on embracing change
and focus a lot on delivering value. In Scrum, the project
has a prioritized backlog of requirements and use iterative
development (called “sprints”) to get basic working software
for the customer to view as soon as possible. Scrum uses
selforganizing teams that get coordinated through daily meetings
called “scrums.” The manager is called a “Scrum Master” to
clarify that it is a facilitating role and not a directive one.</p>
        <p>
          The Scrum methodology consists of three main phases:
Pre-sprint planning, sprint (iteration), and post-sprint meeting.
All work to be done is kept in a “release backlog” where
from requirements (user stories) are taken to the current “sprint
backlog.” The requirements are usually broken down from a
higher abstraction level when the sprint backlog is made. The
actual sprint (usually 2–4 weeks) is when the implementation
is performed. Here, the sprint backlog is frozen and the team
“sprints” to complete what was planned. The team members
choose tasks they want to work on themselves. “Scrum
meetings” also called “Daily scrums” are 15-minute meetings every
morning were the team members check status, report problems,
and keep the whole team focused on a common goal. The
post-meeting is done to evaluate the process and demonstrate
the current system. One important aspect of Scrum is to have
small working teams in order to maximize communication,
minimize overhead, and maximize the sharing of informal (or
tacit) knowledge. The team should also agree and be able to
define when something is considered “done” [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ].
        </p>
        <p>
          c) Lean and Kanban: The flexible project management
techniques and focus on customer value is not new. Within
lean manufacturing these aspects have existed a long time (for
more information about lean manufacturing see for example
[
          <xref ref-type="bibr" rid="ref15">15</xref>
          ]). Many companies combine the process of Scrum with
Kanban (Scrum-ban). It is important to note that Kanban is a
signal card to pull products through the process within Lean
production but has become a software development tool itself
[
          <xref ref-type="bibr" rid="ref17">16</xref>
          ]. Scrum is a more strict process and can be modified
by changing the WIP (work in progress) in each sprint into
being connected to the work-flow state to prevent too much
WIP. Kanban also allows adding items within each sprint.
Another aspect is to change the sprint backlog owned by the
team into a Kanban board with multiple teams with work-flow
state instead. The Kanban board is never reset after a sprint
and can be followed over time, and is also less dependent
on collocation. Scrum only allows three different roles of the
team, while Kanban does not have a limit. Therefore, larger
teams in larger organization with a diversity of specializations
often use Kanban or Scrum-ban when possible [
          <xref ref-type="bibr" rid="ref18">17</xref>
          ].
        </p>
        <p>
          d) Crystal: We will not describe the Crystal
methodologies in detail but, generally speaking, they are built on the
assumption that the main problem in software development is
poor communication. Crystal focuses on people, interaction,
community, skills, talents, and communication as main effects
on performance [
          <xref ref-type="bibr" rid="ref19">18</xref>
          ].
        </p>
        <p>
          The twelve agile principles are a very high-level description
of a work environment. Agile software development is an
ambiguous concept with descriptions on various levels of
abstraction. Many of these are obviously connected to group
dynamics. The problem is that these psychological aspects are
not described in detail in the methods (processes). This means
that this dimension is left out for practitioners to figure our for
themselves to a large extent. In order to try to operationalize
agility and correlate the measurement to group maturity over
time, we enforced the twelve original XP practices (described
in Section II-A0a) on all the participating student teams and
then opted to use the Perceptive Agile Measurement developed
by So and Scholl [
          <xref ref-type="bibr" rid="ref20">19</xref>
          ] in order to measure this “agile” behavior
over time. All the items are included in Section III-E.
        </p>
      </sec>
      <sec id="sec-1-4">
        <title>B. Groups and Teams</title>
        <p>
          A group can be defined as: “three or more members that
interact with each other to perform a number of tasks and
achieve a set of common goals” [
          <xref ref-type="bibr" rid="ref21">20</xref>
          ]. If the group is larger
all the members might not have a common goal, which means
that larger groups often consist of subgroups. Some studies
have shown that smaller groups are more productive than
larger groups with a threshold at around eight individuals [
          <xref ref-type="bibr" rid="ref22">21</xref>
          ].
In psychology, a “work-group” is a group that has a shared
view of the group goal and has developed a structure that
enables goal achievement. A team, on the other hand, is
an effective work-group, however, we will use the terms
somewhat interchangeably in this paper, since agile
workgroups are called “teams” no matter their actual effectiveness.
In social psychology, though, only 17% of all groups were
considered teams according to one study [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ].
        </p>
        <p>
          The group research in psychology received much attention
after the second world war and before the sixties. After
that, the focus in research was on the individual instead
of groups [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ]. The start of the human factors research in
software engineering has also mostly focused on individuals
and their personalities and traits for 40 years without finding
any coherent results [
          <xref ref-type="bibr" rid="ref24">23</xref>
          ]. Therefore, we have reason to believe
that much of what happens in software engineering is set on
team-level, which means that “agility” is hard to obtain if we
do not understand the group dynamics of agile teams, or as
Wheelan and Hochberger [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ] very adequately put it: “before
one jumps to fix something, one has to know what is broken.”
        </p>
        <p>
          During so many years of research on groups in psychology,
there are, of course, a diversity of group development models
[
          <xref ref-type="bibr" rid="ref25">24</xref>
          ]. However, there seems to be a reoccurring patterns of what
happens to all types of groups when humans get together in
order to solve a task. The first researchers to aggregate models
into a general group development model were Tuckman and
Jensen [
          <xref ref-type="bibr" rid="ref26">25</xref>
          ] in the seventies. In the nineties Susan Wheelan
did a similar aggregation of existing models that resulted in
the Integrated Model of Group Development that we used
in this study. However, Tuckman and Jensen’s [
          <xref ref-type="bibr" rid="ref26">25</xref>
          ] model
with the phases; Forming, Storming, Norming, and Performing
correspond well to the stages suggest by Wheelan [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ].
        </p>
      </sec>
      <sec id="sec-1-5">
        <title>C. Wheelan’s Integrated Model of Group Development</title>
        <p>The Integrated Model of Group Development (or IMGD)
describes four different stages that all groups go through
in their journey towards becoming a well-functioning high
performing team. These stages are illustrated in Figure 1 and
described next. The Group Development Questionnaire (the
GDQ), that is a measurement of how much energy the group
is spending on each development stage, is described afterward.</p>
        <p>
          a) Stage 1 — Dependency and Inclusion: During the
first stage of group development (i.e. when the group is new)
the group members have more focus on safety and inclusion,
a dependency on the designated leader, and more of a wish
for order and structure, than in more mature stages. A group
at stage one can still get work done, but will focus more
on figuring out who the other people are. There is a lack
of structure and the group needs to become organized, being
able to do efficient work, and achieve the group goals. The
group members need to create a sense of belonging and lay
the foundation for how to interact within the group. At this first
stage, there is a lack of the feeling of belonging to a group,
but after this stage people start feeling safe enough to state
their ideas and contribute to how they think the group should
work in order to achieve its goals. If this does not happen
groups stagnate, which is often noticed when group members
stop doing work between meetings and even stop attending the
group meetings [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ].
        </p>
        <p>
          b) Stage 2 — Counter-Dependency and Fight: During
the second stage the group starts having conflict. These
differences in opinion is a must in order to create clear roles based
on real competence and to make it possible to work together in
a constructive manner. The group members have to go through
this more turbulent stage in order to build trust. After feeling
safe and therefore daring to have these conflicts, a sense of
loyalty emerges, which is needed to create cohesion. Since we
do not have a clear picture of goals and roles in the beginning,
we need this emotional and hard work in order to get shared
perceptions of values, norms, and goals, which need to be set
on group-level. Since everybody needs to believe in the group
values and norms for them to fill their purpose, the rules of
the game need to be negotiated so that all members thoroughly
believe in them. The more shallow discussions about goals
probably present in the first stage, will now be more emotional
or include disagreements [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ].
        </p>
        <p>
          c) Stage 3 — Trust and Structure: During the third
stage the structure is getting into place and the roles are now
actually based on competence instead of status, power, or
safety concerns. The communication patterns are more open
and also more task-oriented. In this stage the role, organization,
and process negotiations are most often more mature and there
will be an evident clarification and consensus regarding the
group goals. The group members also spend time solidifying
positive relationships, and when the tasks are adjusted to
competence the likelihood of goal achievement is higher. At
this stage the leader’s roll goes from needing to have been more
directive to being more consultative. The communication
structure is also more flexible (i.e. group members talk to whomever
they need). Along the group development the content of the
communication is also more and more task-oriented instead
of relation-oriented. Groups always need the relation-oriented
communication since we always need to do the maintenance
of discussing how we work together as a group. Therefore,
conflict will still occur but be over much faster since the group
has better conflict management techniques. Work satisfaction
and cooperation increase together with cohesion and trust. At
this stage the individual commitment to the group goal will
be higher (i.e. we care about what the group is doing on a
personal level). This means we will see a voluntary conformity
with the norms and helpful deviation from the group (like
subgrouping) will be accepted if considered helpful for the group
as a whole [
          <xref ref-type="bibr" rid="ref27">26</xref>
          ].
        </p>
        <p>d) Stage 4 — Work and Productivity: The forth stage
of group development is when the group does even better
with regards to the purpose of stage three. This means that
the group focuses on getting the task done well together as
well as maintaining group cohesion over a longer period of
time. It is important to realize that there is a large set of
variables that can and will disturb the group development.
Basically, all changes will have such an effect, e.g. change
Stage 1</p>
        <p>Stage 2</p>
        <p>Stage 3</p>
        <p>Stage 4
Dependency
&amp; Inclusion</p>
        <p>CounterDependency
&amp; Fight</p>
        <p>Trust &amp;
Structure</p>
        <p>
          Work &amp;
Productivity
Focus on relationships
and emotions
Focus on work
and productivity
of demands from the organization, losing staff, getting new
staff, and so on and so forth. The challenge in stage four
is therefore to try to maintain the effectiveness reached, and
the most effective groups do not discuss task-related issues a
hundred percent of the time, but actually, still spend around
twenty percent discussing how to work together, which is
key when maintaining high performance. The characteristics
of the decision-making in such teams are participatory and
the team encourages task-related conflicts, since they help
finding better solutions to problems faced. A person who
is or has been on such a team will recognize the intensity
of the work and the effectiveness together with a very high
interpersonal attraction between group members. People in
such high performing teams often look at their work with
excitement and joy and getting work done is easy and members
have the feeling of being a part of the absolute best team in
the world. Getting to stage four takes a lot of work both from
internal group members but the group also needs to be given
the right conditions from their surrounding ecosystem [
          <xref ref-type="bibr" rid="ref27">26</xref>
          ].
        </p>
      </sec>
      <sec id="sec-1-6">
        <title>D. The Group Development Questionnaire (GDQ)</title>
        <p>
          Wheelan [
          <xref ref-type="bibr" rid="ref27">26</xref>
          ] was not the first one who found these
characteristic stages of group development, but she contributed
with a tool to measure these different stages with four scales
put together in a questionnaire. Her tool has made it possible
to measure and therefore diagnose where a specific group is
focusing its energy from a group developmental perspective. The
survey has a total of 60 items and provides a powerful tool for
research and interventions in teams. Scale four (GDQ4) is the
“work and productivity” and has been shown to correlate with
a set of effectiveness measures in different fields. Examples
are that groups that have high scores on GDQ4 finish projects
faster [
          <xref ref-type="bibr" rid="ref28">27</xref>
          ], students perform better on standardized test (SAT
scores) if the faculty team scores high on GDQ4 [
          <xref ref-type="bibr" rid="ref29">28</xref>
          ], [
          <xref ref-type="bibr" rid="ref30">29</xref>
          ],
and intensive care staff save more lives in surgery [
          <xref ref-type="bibr" rid="ref31">30</xref>
          ].
        </p>
      </sec>
      <sec id="sec-1-7">
        <title>E. Technology under investigation</title>
        <p>
          The group development stages have been well-known for
many years in social psychology [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ]. Helping teams to
develop and mature in their group development have been
shown to increase productivity and effectiveness in a diversity
of fields (see Section II-D). Therefore, we want to see if
helping teams to mature from a group psychology perspective
also gets them to mature in their usage of the XP practices.
        </p>
        <p>
          There are many group development models, but few have
been scientifically validated in the way the group development
questionnaire (GDQ) has [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ]. Since correlations have been
found between the group score on the “work and
productivity” scale of the GDQ and other external effectiveness
measurements, it would interesting to explore its effect on
agile software development teams in their adoption of agile
practices. Especially since agile methods have been shown to
increase software development project success [
          <xref ref-type="bibr" rid="ref32">31</xref>
          ].
        </p>
        <p>
          Evidence-based interventions within group development
with the GDQ have been shown to increase the group maturity
in teacher teams [
          <xref ref-type="bibr" rid="ref33">32</xref>
          ], and to increase the velocity of group
development [
          <xref ref-type="bibr" rid="ref34">33</xref>
          ].
        </p>
      </sec>
      <sec id="sec-1-8">
        <title>F. Relevance to practice</title>
        <p>If group development training can be shown to increase the
agility of software engineering teams, such aspects would be
appropriate to explicitly integrate into the implementation of
“agility” in all organizations conducting software development.</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>III. EXPERIMENT PLANNING</title>
      <sec id="sec-2-1">
        <title>A. Goals</title>
        <p>The goal of this experiment was to see if training an agile
team in group developmental psychology would increase their
agility through more mature use of the agile practices.</p>
      </sec>
      <sec id="sec-2-2">
        <title>B. Experimental units</title>
        <p>In order to conduct an experiment the study was conducted
with 43 students in an agile software development course at the
University of Sa˜o Paulo. Group developmental aspects apply to
all group-work and therefore working with students as research
subjects is a valid representation of software development
conducted by developers on all knowledge levels. However,
we would still be careful in generalizing a result to a larger
population than that of developers in the phase of learning an
agile approach (i.e. individuals with little experience of agile
software development in practice). The course were offered
to 3rd year students, however, most students usually take the
course in the 4th or 5th (last) year of their software engineering
degree. The course is also open to graduate students who
are given the possibility to take the course twice during their
graduate education.</p>
        <p>The student teams in this study comprised students
enrolled in a project XP software development course called
“The Laboratory of XP” at the Institute of Mathematics and
Statistics at the University of Sa˜o Paulo. The purpose of the
course is to introduce agile methods through the use of XP.
These methods included, at a minimum, the twelve practices
presented in Section II-A0a. Some other staff at the university
acted as customers and had to pitch their project ideas to the
students, who signed up for the most interesting one from their
point of view. All the teams included six to eight members
and a more experienced student acting as a an agile coach for
the team. The process was put together by the student teams
themselves and we allowed any type of additional practices
they selected as long as it was within the XP framework. As
an example, we enforced collocation of a minimum of eight
hours per week.</p>
      </sec>
      <sec id="sec-2-3">
        <title>C. Experimental material</title>
        <p>The experimental object was the agile software
development team. Group norms and cooperation are set on group
level and therefore the actual “team” is the relevant level of
analysis.</p>
      </sec>
      <sec id="sec-2-4">
        <title>D. Tasks</title>
        <p>The experimental tasks applied in this experiment was for
the teams (one team at a time) to listen and reflect on group
development theory and discuss its applicability in connection
to their own team.</p>
      </sec>
      <sec id="sec-2-5">
        <title>E. Hypotheses, parameters, and variables</title>
        <p>
          The construct used to measure agile practices and the
behavior connected to them, was the mature usage of nine
agile practices as defined by So and Scholl [
          <xref ref-type="bibr" rid="ref20">19</xref>
          ]:
        </p>
        <p>Iterative Planning: (1) All members of the technical team actively
participated during iteration planning meetings. (2) All technical team members took part
in defining the effort estimates for requirements of the current iteration. (3) When
effort estimates differed, the technical team members discussed their underlying
assumption. (4) All concerns from team members about reaching the iteration
goals were considered. (5) The effort estimates for the iteration scope items were
modified only by the technical team members. (6) Each developer signed up for
tasks on a completely voluntary basis. (7) The customer picked the priority of the
requirements in the iteration plan.</p>
        <p>Iterative Development: (1) We implemented our code in short iterations. (2)
The team rather reduced the scope than delayed the deadline. (3) When the scope
could not be implemented due to constraints, the team held active discussions on
re-prioritization with the customer on what to finish within the iteration. (4) We
kept the iteration deadlines. (5) At the end of an iteration, we delivered a potentially
shippable product. (6) The software delivered at iteration end always met quality
requirements of production code. (7) Working software was the primary measure
for project progress.</p>
        <p>Continuous Integration and Testing: (1) The team integrated continuously.
(2) Developers had the most recent version of code available. (3) Code was checked
in quickly to avoid code synchronization/integration hassles... (4) The implemented
code was written to pass the test case. (5) New code was written with unit tests
covering its main functionality. (6) Automated unit tests sufficiently covered all
critical parts of the production code. (7) For detecting bugs, test reports from
automated unit tests were systematically used to capture the bugs. (8) All unit
tests were run and passed when a task was finished and before checking in and
integrating. (9) There were enough unit tests and automated system tests to allow
developers to safely change any code.</p>
        <p>Stand-Up Meetings: (1) Stand up meetings were extremely short (max. 15
minutes). (2) Stand up meetings were to the point, focusing only on what had
been done and needed to be done on that day. (3) All relevant technical issues
or organizational impediments came up in the stand up meetings. (4) Stand up
meetings provided the quickest way to notify other team members about problems.
(5) When people reported problems in the stand up meetings, team members
offered to help instantly.</p>
        <p>Customer Access: (1) The customer was reachable. (2) The developers could
contact the customer directly or through a customer contact person without any
bureaucratic hurdles. (3) The developers had responses from the customer in a
timely manner. (4) The feedback from the customer was clear and clarified his
requirements or open issues to the developers.</p>
        <p>Customer Acceptance Tests: (1) How often did you apply customer
acceptance tests? (2) A requirement was not regarded as finished until its acceptance
tests (with the customer) had passed. (3) Customer acceptance tests were used as
the ultimate way to verify system functionality and customer requirements. (4) The
customer provided a comprehensive set of test criteria for customer acceptance. (5)
The customer focused primarily on customer acceptance tests to determine what
had been accomplished at the end of an iteration.</p>
        <p>Retrospectives: (1) How often did you apply retrospectives? (2) All team
members actively participated in gathering lessons learned in the retrospectives.
(3) The retrospectives helped us become aware of what we did well in the
past iteration/s. (4) The retrospectives helped us become aware of what we
should improve in the upcoming iteration/s. (5) In the retrospectives (or shortly
afterwards), we systematically assigned all important points for improvement to
responsible individuals. (6) Our team followed up intensively on the progress of
each improvement point elaborated in a retrospective.</p>
        <p>Collocation: (1) Developers were located majorly in... (2) All members of
the technical team (including QA engineers, db admins) were located in... (3)
Requirements engineers were located with developers in... (4) The project/release
manager worked with the developers in... (5) The customer was located with the
developers in...</p>
        <p>
          The group maturity (or effectiveness) operationalization
was done through using Scale 4 of the GDQ [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ]. All the
items in the GDQ scale cannot be shared here due to copyright,
however, we can include three example items:
        </p>
        <p>The group gets, gives, and uses feedback about its
effectiveness and productivity.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>The group acts on its decisions.</title>
      <p>This group encourages high performance and quality
work.</p>
      <p>The group development measurement on Scale 4 was
assessed on a 5-point Likert scale (1 = low agreement to
the statement and 5 = high agreement). The agile items
were assesses on a 7-point Likert scale (1 = never and 7 =
always). These scales were used for the simple reason that
these measurements were developed and validated using these
exact scales.</p>
      <p>
        Both measurements have been validated using a factor
analysis [
        <xref ref-type="bibr" rid="ref35">34</xref>
        ] and a test for internal consistency (using the
Cronbach’s [
        <xref ref-type="bibr" rid="ref36">35</xref>
        ]).
      </p>
      <p>The formal research hypothesis for each scale is that
the mean values for the scale is different between the two
measurements, or H1 : 1 6= 2.</p>
      <sec id="sec-3-1">
        <title>F. Design</title>
        <p>We used a longitudinal research design in order to test
differences in group mean value scores on the two measurements
over time. The first measurement comprised seven teams and
43 student responses, and the second measurement comprised
the same seven teams with 40 responses, i.e. three student were
absent during the second measurement.</p>
      </sec>
      <sec id="sec-3-2">
        <title>G. Procedure</title>
        <p>The two measurement surveys were distributed to the
teams five weeks into their software development projects
(during their scheduled and collocated development sessions).
The reason was to let the students actually form teams and
have done some work before the first measurement. Three
of the participating seven teams were randomized into the
experimental group and the remaining four teams were used as
a control group. The randomization was done by first writing
the numbers “3” and “4” on paper slips and letting a person
not connected to the experiment draw one folded slip for the
research group (three groups were selected). The second step
was conducted by writing all team names on other paper slips
and letting the person draw three slips to be used for the
research group.</p>
        <p>
          On week six, the three selected teams participated in a
1.5-hour group development training with a discussion on
the applicability to their own team. During the first hour
of the training, the first author of this paper presented The
Integrated Model of Group Development [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ] and its four
group developmental stages. The idea is, briefly, that there are
predictable group developmental stages that all groups have
to go through in order to work effectively. If team-members
are aware of these there is a smaller probability of the team
getting stuck on group issues, which leads to quicker and
higher quality work [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ]. Aspects covered were, for example,
goal-setting, role clarification, decision-making, and leadership
issues of groups in different development stages.
        </p>
        <p>On week eleven, the second measurement was conducted
using the same procedure as in the first measurement.</p>
      </sec>
      <sec id="sec-3-3">
        <title>H. Analysis procedure</title>
        <p>IV.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>RESULTS</title>
      <sec id="sec-4-1">
        <title>A. Descriptive statistics</title>
        <p>Since we aimed at affecting the agile practices score by
conducting group psychology training, we first looked at if we
managed to increase the group dynamics score. Since that was
not the case we already knew we did not succeed with the
intended plan of the experiment. However, we still looked for
differences in the agile practices measurement to see if they
differed anyways between the two measurements. The only
two significant differences we found between the first and
second measurements were that the scales “Retrospectives”
and “Customer Acceptance Tests.” Therefore, we show the
descriptive statistics for these scales as well (see Table I).</p>
      </sec>
      <sec id="sec-4-2">
        <title>B. Data set preparation</title>
        <p>
          A mean value was calculated based on the collected data
for each individual, and then for the team according the agile
practices as defined by So and Scholl [
          <xref ref-type="bibr" rid="ref20">19</xref>
          ]. The measured
agile practices were: Iteration planning, Iterative development,
Continuous integration and testing, Stand-up meetings,
Customer access, Customer acceptance tests, Retrospectives and
Collocation. The group development Scale 4 individual items
were also turned into a mean value for each individual and then
for the groups separately. Since we wanted to run the analysis
on group-level we only have three mean values in the research
group and four values in the control group (seven groups in
total).
        </p>
      </sec>
      <sec id="sec-4-3">
        <title>C. Hypothesis testing</title>
        <p>
          Since we have so few data points, we cannot assess the
population distribution based on our sample. However, other
studies have shown this kind of data to be normally distributed
[
          <xref ref-type="bibr" rid="ref20">19</xref>
          ], [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ]. Also, since we did not find any significant results
based on parametric tests, neither would we for non-parametric
tests (since they are more restrictive). We began by testing the
group effectiveness score (GDQ4 mean values) for the first
and second measurements and can conclude that we did not
see a significant effect (see Table II).
        </p>
        <p>We then, still, ran the same analysis for all the agile
practices and only found that the scales “Retrospectives” and
“Customer acceptance tests” were different between the two
measurements overall and not in connection to whether they
were in the research group or not (see Table III and Table IV).</p>
        <p>We conclude that the group development effectiveness
measurement (GDQ Scale 4) was not different between the
research group and the control group (not in the first nor
the second measurement). The two agile practices
“Retrospectives” and “Customer acceptance tests” where both different
overall between the two measurements, but not depending on
if the teams were in the research group or the control group.</p>
        <p>The data was analyzed using a general linear model for
repeated measures (i.e. a standard repeated measures ANOVA).
Such a model assumes normality in data, but since we did not
find any significant result, we did not proceed to use
nonparametric tests (since these are more restrictive and would
therefore neither show any significance).</p>
        <p>We did not find any of the expected results in this study.
Clearly, just having 1.5 hours of training and discussion is
not enough to help the group to develop, even if 1.5 hours of
a workweek of 8 hours (like the students in the course had)
would be equivalent to 7.5 hours of working full-time 40 hours
a week. When taking a closer look at when other experiments</p>
        <p>TABLE III. ANOVA FOTeRTsTtesHsEotsfTWoWfiOtWhRiinEt-hPSiEunAb-TSjeEucDbtsjReCEcTotsRnOtCrSaoPsnEttsCraTsIVtsES MEASUREMENTS.
Meeaassuurree:: MMEEAASUSURER_E1_1
succeeded in significantlMyeasure: MEASUgRrEo_1ups to develop and
helping the</p>
        <p>Partial Eta
capture their increased mSoautrucreity, it turns oCuatt they diSdquamreduch
a
larger intervention then Cwatas applied in thLiinseasrtudy. Jaco b.5s8so4n
and Wramsten Wilmar [3C2a]t, *for example, gLainveearthe groups eight
different interventions orfesgeraorcuhp_gdroeuvpelopment assessmen.t1a4n5d
enforced improvement pEorrionrt(sCatth) at the groLuinpeahrad to work on
until the next workshop, plus the students were fully dedicated
to only one course. In hindsight, we probably would have
needed something similar in order to move the groups forward
in the research group. There is also, of course, the possibility
of software engineering teams’ agility not being as dependent
on group maturity as we might think.</p>
      </sec>
      <sec id="sec-4-4">
        <title>A. Threats to validity</title>
        <p>
          We believe the layout of the experiment has potential. Of
course, even if we would have found a significant difference,
we would still have to have been careful when generalizing
the results due to the very small sample size. Regarding
construct validity the first author was present during the data
collection and could answer any potential questions regarding
the questionnaire. However, since we did not want the control
group to get training of group development we provided all
participants with as little information as possible before the
first survey, since we did not want to introduce bias. The
tradeoff is of course that the participants could have misinterpreted
the questions and failed to answer in connection to our
intended operationalization of constructs. Regarding learning
effects between measurement, the GDQ has been shown to
be stable for repeated measurements as such [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ]. We have
no such studies for the agile practices, which means that we
might have seen a learning effect when students answer that
part of the survey.
        </p>
        <p>
          In order to prevent hypothesis guessing, we only informed
the participant that the research was about looking at
connections between group psychology and agile practices and not
more detail on how we expected them to be connected. The
internal validity is considered quite high in this experiment
since we used validated scales as defined and validated
quantitatively by other researchers [
          <xref ref-type="bibr" rid="ref20">19</xref>
          ], [
          <xref ref-type="bibr" rid="ref23">22</xref>
          ]. However, inter-group
communication between the research groups and the control
groups is also a threat our experimental research design.
Page 1
        </p>
        <p>We draw no inference from this experiment. We do not
want to state that group development causes more mature use
of agile practices, nor the opposite. Page 1
.002
.034
.797
.399
.584
.145</p>
      </sec>
      <sec id="sec-4-5">
        <title>B. Lessons learned</title>
        <p>
          The largest lesson learned from this experiment is evidently
to check the level of intervention effort needed to move
groups forward in their development before conducting this
kind of an experiment. We still do not known the effort
needed, but the span is more then one 1.5 hours workshop
with a second measurement two months later, and less than
six to eight workshops of 2–3 hours during a full year with
connected action plans and follow-up. By having more time
with the teams we could have focused even more concretely on,
for example, goal-setting, role clarification, decision-making,
functional sub-grouping, or leadership issues, like in [
          <xref ref-type="bibr" rid="ref33">32</xref>
          ].
        </p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>CONCLUSIONS AND FUTURE WORK</title>
      <p>We obtained an insignificant result of this experiment.
We therefore have no conclusions to draw based on the
expected effects. However, we believe these concepts could
still be connected since agile software development is based
on teamwork to a large extent. We evidently need a larger
intervention effort and, of course there could also be more
confounding or mediating factors we have not thought of in
the context of agile software development teams.</p>
      <p>
        We would like to redo this experiment with more resources
and be able to give the teams in the research group eight times
more workshops with connected action plans in order to see
if we can get a similar effect as has been shown with teacher
teams [
        <xref ref-type="bibr" rid="ref33">32</xref>
        ]. It would, of course, be advantageous to include
as many teams as possible and at multiple universities and
companies to increase the statistical power of the experiment.
      </p>
    </sec>
  </body>
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