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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>How to Design Experimental Research Studies around Digital Badges</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Rudy McDaniel</string-name>
          <email>rudy@ucf.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Joseph R. Fanfarelli</string-name>
          <email>joseph.fanfarelli@ucf.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Central Florida</institution>
          ,
          <addr-line>P.O. Box 161990, Orlando, FL 32816</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2015</year>
      </pub-date>
      <abstract>
        <p>Digital badging is becoming more popular in an assortment of disciplines, both academic and professional. Along with the success of practical badging initiatives, badging research is also moving at a rapid pace, a rate of change that may be intimidating to the uninitiated wishing to study them. However, there is a great need for additional research in light of the complexity of badging and the many contexts in which badging occurs. This paper outlines an approach to designing research studies around digital badges to assist researchers who are new to the field and looking to contribute. It begins by discussing how to form relevant research questions and how to approach the literature review, providing useful references as starting points. It then continues on to experimental design recommendations, discusses useful practices during experimentation, and concludes with recommendations for data analysis. Additionally, this paper describes challenges that are specific to badging and places them in context of the research design process. Multiple examples are provided to clarify these concepts.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Digital Badging</kwd>
        <kwd>Education</kwd>
        <kwd>Learning</kwd>
        <kwd>Motivation</kwd>
        <kwd>Goal Setting</kwd>
        <kwd>Credentials</kwd>
        <kwd>Assessment</kwd>
        <kwd>Experimental Design</kwd>
        <kwd>Research Design</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>
        Digital badging initiatives have gained traction in multiple
professional domains and for a number of purposes. As
evidenced by their use as digital credentialing technologies
[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], reward systems [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], and as tools in other scenarios,
badging is an emerging practice containing several
dimensions ripe for study. However, good badging studies
require researchers to make a number of careful decisions
that can seem overwhelming for those new to the subject.
      </p>
      <p>
        Badging research often spans multiple disciplines including
psychology, computer science, educational technology, and
the visual arts. As a result, some researchers from
disciplines not trained in research methods may wish to
learn basic strategies for conducting quantitative research
so that we can more fully understand badge design and
function, in an empirical sense, across academic
boundaries. While researchers working in disciplines such
as psychology and educational technology may already be
well versed in experimental research design, those working
in other fields may not. To address this issue and to provide
context for the unique aspects of badging research, this
paper situates badge-specific recommendations within the
context of general good research practice. Overall, the
purpose of this paper is to outline an approach for
designing and developing badge-based research protocols
based on our prior experiences developing and
administering several such studies [3], [
        <xref ref-type="bibr" rid="ref3">4</xref>
        ], [5]. This is
accomplished by discussing the research process as it
relates to studies specifically designed around digital
badges. Topics discussed include developing appropriate
research questions for badges, considering how to develop
dependent variables in these contexts, and recognizing the
unique characteristics of badge-based data analysis.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. DEVELOPING THE RESEARCH</title>
    </sec>
    <sec id="sec-3">
      <title>QUESTIONS</title>
      <p>Badges are used for a variety of purposes, from
incentivizing actions and behaviors to tracking performance
outside normal channels of assessment and evaluation.
They are also used in a variety of settings and for many
purposes, from informal science learning in museums or
wilderness scouting programs to formal coursework in the
public school system and higher education.</p>
      <p>Thus, when designing research questions for a badging
study, it is useful to first consider the context and
mechanics of the badging system. Before honing in on
particular research questions, for example, several more
general areas should first be considered. The following
procedural prompts are useful for thinking about how a
research study might be generally framed, and then later
operationalized, through more specific questions:
What is the context of the badging system? In other words,
how is the badge system being used? Is it deployed in a
children’s museum for the purposes of informal science
learning? Is the system integrated into a learning
management system for the purpose of motivating
undergraduate college students? Are badges being used in
conjunction with a mobile fitness app to encourage healthy
lifestyle choices? The overall context for the badging
system is important to consider up front as a necessary
precursor to the formation of specific research questions.
Who will design the badges? Will the experimenter design
them? As an expert in the literature, the experimenter may
be able to develop the most scientifically sound system.
However, the experimenter is likely not as well-suited for
design tasks such as graphic design or textual layout. In
addition, design heuristics for badging research are still
lacking. While past studies have developed some
promising general guidelines, comprehensive blueprints for
successful badge design for specific circumstances do not
yet exist.</p>
      <p>Is it necessary for the designer to have a relationship with
the end users? While a researcher may understand the
current state of badging knowledge, an educator may have
a better understanding of the curriculum, the tasks with
which her students are having difficulty, and knowledge
about what motivates those students.</p>
      <p>Who is awarding the badges? In other words, what is the
central badging authority within a system? Badges can be
provided for many reasons. They can be objective (e.g., a
learner received a score of 90% or better) or subjective
(e.g., a learner demonstrated exceptional effort on an
assignment). The question of badge authority is especially
important for subjective badges. Subjectivity, by definition,
is ambiguous and open to interpretation. Thus, the
perception of exceptional effort may differ by instructor.
There are a number of other guiding questions that are also
useful for research design, but these are some of the more
common prompts likely to be helpful across a variety of
study types. The ways in which these questions are
answered will influence the way research hypotheses are
formed. As always, it is important to be clear and detailed
in the formation of these experimental research questions.
It is also important to be precise during the
preexperimental phase of the study in regards to the unique
aspects of the badging system under investigation.
By formulating clear research questions at the onset, one
can better determine the particular approach and
instruments with which to design the study protocol. The
research questions should take into account both the
objectives of the research and the environmental factors in
•
•
•
•
•
•
which the research is occurring. They should additionally
consider the audiences the investigators will have access to.
For example, in addition to the unique decisions made
regarding the badging process, a study might be designed
around the following research questions:</p>
      <p>How do badges affect motivation toward group
projects in an online course focused on introductory
psychology?
Do students who earn more badges perform better in
the course, as evidenced by earning higher grades?
The questions should be specific and measurable and may
be explored through different types of research designs. In
general, although the research questions may be refined
after conducting the literature review, the overall purpose
for the research should be decided upon at the beginning of
the research process. This purpose will set the stage for the
remainder of the protocol design.</p>
      <p>
        In addition to the impact and influence of badges, the
researcher might also identify the type of badging system
they wish to study in the formulation of his or her research
questions. For instance, if the aim is to compare open badge
systems such as Mozilla’s Open Badges to a proprietary
badging system developed by a commercial vendor, the
following research questions might be more appropriate:
Are students more likely to consider badges useful
when they can be permanently displayed outside of the
course, even after completing their coursework?
Are there differences in motivation or engagement
toward course modules in students who use badge
system A as compared to badge system B?
Another method of studying badges is in regards to their
operational components. As Hamari and Eranti [
        <xref ref-type="bibr" rid="ref18">6</xref>
        ] explain,
badges can be broken down into three primary components:
a signifier, a completion logic, and a reward. These parts
can each be considered separately within the design of a
study to investigate badges using a finer degree of
granularity. For example, here are two potential research
questions focusing on separate components of badging
according to Hamari and Eranti’s framework:
      </p>
      <p>
        What visual signifiers are most effective for capturing
the attention of players in the badges used within a
racing-themed video game?
How does the perceived degree of difficulty within the
completion logic of puzzle-based games impact player
enjoyment of those types of games?
There is a theoretically infinite number of potential
research questions to be explored by badging studies. This
flexible, purpose-driven research question generation
process presents opportunities for badging studies to
connect with or augment other research in areas such as
sociology, psychology, or digital media and industrial
design. For example, while badges are frequently thought
of as rewards or credentialing systems, they can also
perform a number of other roles, serving as goal-setting
mechanisms, social status indicators, and group identifiers
[
        <xref ref-type="bibr" rid="ref19">7</xref>
        ]. Design cues can be tweaked as necessary to serve each
of these purposes more readily and empirical data can
suggest particular areas of the user interface in which to
concentrate.
      </p>
    </sec>
    <sec id="sec-4">
      <title>3. Literature Review</title>
      <p>
        After the research questions have been formulated, it is
time to plan out the specifics of the study. This cannot be
effectively executed without a good working knowledge of
the literature. As with any study, a thorough literature
review is necessary to identify the conclusions of previous
research and to discover what is not yet understood. New
badging articles are being published frequently, so it is
important to stay current with the latest developments in
the field. In particular, annotated bibliographies focused on
gamification (e.g., [
        <xref ref-type="bibr" rid="ref4">8</xref>
        ]) and digital badges (e.g., [
        <xref ref-type="bibr" rid="ref5">9</xref>
        ]) are
valuable, as are studies outlining prior implementations of
badges and the lessons learned through those experiences
(e.g., [
        <xref ref-type="bibr" rid="ref6">10</xref>
        ]). Articles focused on the required and optional
components and qualities of badges [
        <xref ref-type="bibr" rid="ref18">6</xref>
        ] can provide a
deeper understanding of badges while also providing ideas
for elements that can be manipulated during
experimentation.
      </p>
      <p>The diverse nature of badging, in combination with the
frequency of new publications, can often make finding
relevantly focused research difficult. Fortunately, the
desired functionality of the system (e.g., reward or
credentialing) has already been decided upon when
formulating research questions. This can serve as a guide
for appropriately narrowing the literature review from a
large but broad set of results to a more narrow and precise
body of work. The literature review might begin with
research related to the broader focus of the research
questions, such as badge motivation, reward, or
credentialing. One needs to branch out to other relevant
fields after this literature has been exhausted. For example,
if badges are being studied as rewards with a specific
emphasis on their potential to improve motivation, one may
consider browsing the psychology-based literature to learn
more about theories of motivation. Or, if credentialing is
the focus, research on professional certifications may yield
relevant knowledge. As digital badging is a fairly new field
of study, it is possible that the specific research on digital
badging related to the chosen topic may be sparse or even
nonexistent. Considering broader areas or related
disciplines of study will enable the discovery of knowledge
that is potentially transferrable and may yield insights that
prove valuable during hypothesis formation and
experimental design.</p>
    </sec>
    <sec id="sec-5">
      <title>4. EXPERIMENTAL DESIGN</title>
      <p>After assimilating relevant background
experimental design can begin.
knowledge,</p>
    </sec>
    <sec id="sec-6">
      <title>4.1 Experimental Manipulations</title>
      <p>Since the specific badging functionality has already been
selected by this point in the research design, identifying the
experimental manipulations should not be overly taxing.
Just as with any other experimental study, a control and
experimental group will be necessary.</p>
      <p>There are some unique concerns which should be thought
through, however. For instance, if individual badges are
beings studied, the experimenter should record, without the
participants’ knowledge, who would have earned the
badges had the badging system been implemented in the
control. This will enable a comparison between those who
completed the requirements for earning the badge of
interest and received it against those who completed the
requirements and did not receive it. Otherwise, it will not
be possible to know if differences in the dependent
variables between the control and experimental groups
were due to the presence or absence of the badge itself, or
due to some other factor associated with completing the
requirements for earning the badge.</p>
    </sec>
    <sec id="sec-7">
      <title>4.2 Demographics</title>
      <p>
        Individual differences appear to be present in badging [
        <xref ref-type="bibr" rid="ref19">7</xref>
        ],
[5], [
        <xref ref-type="bibr" rid="ref7">11</xref>
        ], but the results are not yet conclusive. It is
important for future studies to continue to collect
demographic data in order to understand how badges are
perceived of and received by learners of varying genders
and ethnicities.
      </p>
      <p>
        Additionally, badging does include some novel
demographic concerns that have implications for
demographic survey design. For example, in response to
the proliferation of badging in video games [
        <xref ref-type="bibr" rid="ref8">12</xref>
        ], [
        <xref ref-type="bibr" rid="ref9">13</xref>
        ], [
        <xref ref-type="bibr" rid="ref10">14</xref>
        ],
video game players may have much more experience with
badging than other participants. In games, badges may also
be known as achievements or trophies. Since the effects of
prior interaction with badging are not yet known, it can be
helpful to include a question or instrument to assess the
extent of prior interactions with games to aid the analysis of
any unexpected results at the end of experimentation.
Having this information will allow researchers to control
for prior gaming experience within the sample during the
data analysis phase.
      </p>
    </sec>
    <sec id="sec-8">
      <title>4.3 Dependent Variables</title>
      <p>
        A variety of dependent variables are relevant to badging
studies, but some have received more interest than others.
When badges are studied as rewards, intrinsic motivation
[
        <xref ref-type="bibr" rid="ref11">15</xref>
        ] is commonly measured as an indicator of the
participants’ desire to complete the task simply for the
reward of having completed the task. This is in contrast to
extrinsic motivation which refers to the participants’ desire
to complete the task in order to gain some external reward
such as money or a trophy. Intrinsic motivation is typically
measured through the interest/enjoyment subscale of the
intrinsic motivation inventory [
        <xref ref-type="bibr" rid="ref12">16</xref>
        ].
      </p>
      <p>
        Learner engagement is another dependent variable that
serves as an indicator of the participants’ willingness to
take an active role in the experimental task. This construct
can be measured using questionnaires like the Classroom
Survey of Student Engagement [
        <xref ref-type="bibr" rid="ref13">17</xref>
        ], the Student Course
Engagement Questionnaire [
        <xref ref-type="bibr" rid="ref14">18</xref>
        ], or, for game and
simulation-based studies, an engagement questionnaire
[
        <xref ref-type="bibr" rid="ref15">19</xref>
        ]. Engagement can also be measured in terms of
participants’ level or frequency of activity on the
experimental task. This might be indicated by the number
of answers submitted, the number of times logged into the
system, or the number of minutes spent on task.
      </p>
      <p>Badges are frequently implemented to improve
performance, so performance measures can also serve as
dependent variables. The specific metrics used will depend
heavily on the experimental task. In education studies,
participants’ final grades are typically appropriate data
points to collect. Accuracy, as a ratio of correct to incorrect
answers or classifications, is another popular metric that
extends beyond academic environments. The researcher
should consider which metrics best indicate success or
failure in the environment being studied.</p>
      <p>In some instances, badges themselves can be used as
dependent variables. For instance, the number of badges
earned may be a useful metric in correlational studies.
Perhaps, as learners earn more badges, their perceived
selfefficacy increases. Or, participants who earn more badges
may exhibit more goal-directed behavior. If these questions
are of interest to a researcher, they can be formulated as
guiding research questions at the beginning of a research
study’s design (see Section 2).</p>
    </sec>
    <sec id="sec-9">
      <title>5. SELECTING A BADGING SYSTEM</title>
      <p>Selecting a badging system for an experiment is one of the
most important tasks in designing a badging study. The
chosen system will influence major aspects of the protocol
including the risks of the study and the capabilities in
badging experimentation. There are two primary routes: 1)
Develop a system or hire a developer to develop the
system; or 2) Use a commercial system that has already
been developed.</p>
    </sec>
    <sec id="sec-10">
      <title>5.1 Developing a System</title>
      <p>
        Developing a badging system provides the greatest range of
capabilities. When a system is developed from scratch, it
can be built to exact specifications with the exact badging
features one needs for a particular group of users. This is
important because there is evidence to suggest that badging
systems must be well-designed in order to fulfill their
intended function [
        <xref ref-type="bibr" rid="ref2 ref3">2, 4</xref>
        ].
      </p>
      <p>It is certainly possible to design and implement one’s own
system, but this may require skills outside of one’s
capabilities. Designing a badging system on one’s own
requires a number of diverse skills including programming,
database design, graphic design, and instructional design. A
background in writing or technical communication is also
useful to determine the most effective methods for
structuring verbal and visual information within the context
of badges.</p>
      <p>When in-house developing prowess is insufficient, an
external developer is needed to develop the badging
system. In this scenario, it is obviously better to hire
experienced developers if at all possible. With these
professionals, finishing the system on time is more likely
than it is in developing one’s own system. Moreover, the
same flexibility can be included in the developed system
since it is still being developed from scratch to meet the
specifications of the customer. If, however, development
costs are high and budgets are small, hiring an experienced
developer may not be an option. Or, financing the
development of a very limited system may be the only
possibility.</p>
      <p>When working with a badge system developer,
communication becomes very important. If the system’s
specifications are not well understood by the developer,
errors may be made which could delay development or
result in a system which does not meet the researcher’s
standards. Furthermore, bugs and specification
discrepancies may not be discovered until experimentation
has already begun, introducing variations that introduce
minor confounds or even completely invalidate the data.
This was the case with one of the authors’ prior studies.
They found out after the study had concluded that the
participants enrolled in the non-badging section of a course
were all emailed the same badge award notifications that
the participants in the badging section received. This was
problematic because the badges did not actually exist for
those users enrolled in the non-badging section. A glitch in
the badging system therefore led to problems with the
separation between badging and non-badging sections of
the course, leading to unreliable data.</p>
      <p>It should be noted that either of these methods for
developing a customized system comes at a cost. These two
models provide the utmost flexibility for researchers, but
they both require overhead that often makes this method of
design impractical. It may take too long to develop a
system that meets the needs of the experimenter. Or, it may
be too expensive. In these instances, the enhanced
flexibility may not be justified by the necessary resources
to enable that flexibility. Further, if strict deadlines exist,
attempting to develop a system in time to meet the study’s
goals will introduce a moderate level of risk into the study.</p>
    </sec>
    <sec id="sec-11">
      <title>5.2 Using a Commercial System</title>
      <p>When working with a tight budget or a strict timeline, a
commercial system may be the only viable option. Here,
the researcher will choose one of several commercially
available badging solutions. These systems typically offer
limited customization and may or may not require a fee,
though this fee is typically very small in comparison to the
cost of developing a new system. Perhaps the largest
benefit of commercial systems is that they are already
developed and the majority of their bugs have already been
corrected. These systems also offer good transparency in
terms of features. The limitations and affordances are
immediately apparent.</p>
    </sec>
    <sec id="sec-12">
      <title>6. DURING EXPERIMENTATION</title>
      <p>Experimentation in badging studies is very similar to other
human-in-the-loop studies, but requires some special
considerations. It is important for the experimenter to be
aware of the special considerations of badge research and
be prepared to record any unplanned events or unexpected
observations regarding the badge system. Researchers
administering badge-specific studies may want to pay
particular attention to these three dimensions of complexity
during the study.</p>
    </sec>
    <sec id="sec-13">
      <title>6.1 Technical and operational complexity</title>
      <p>As with any digital system, badging systems have the
capacity to malfunction. This may happen due to problems
within the software or usability issues with the participants.
While the best course of action is to thoroughly test the
system to avoid such issues before experimentation begins,
bugs may still end up in the experimental system,
potentially compromising the data. Once experimentation
begins, the system should be regularly monitored and
evaluated to identify any errors that arise. For instance, a
participant may mention receiving a badge that they did not
earn, or not receiving a badge that they did earn. If the
experimenter decides that the participant is correct, the
malfunction is obvious and may be quickly remedied (after
a note is made to evaluate the impact of this confound).
However, participants may not be familiar with the
criterion for earning a badge, or the criterion may be too
subjective for the participant to make a confident decision.
As a result, the experimenter should routinely check to
ensure that the badges are being awarded in the way that
was designed. This can ensure that errors are caught early
and can be accounted for during data analysis.</p>
    </sec>
    <sec id="sec-14">
      <title>6.2 Behavioral complexity</title>
      <p>Participant behaviors in these types of studies can be very
informative. Especially if the experiment only lasts for a
short duration and the experimenter and participants are
colocated, it is helpful to record behavioral observations.
Noticing behaviors that are indicative of changes in
dependent variables can provide useful information for data
interpretation or ideas for future experimentation. For
example, participants shouting in frustration or satisfaction
may be showing indicators of engagement or immersion.
Or, if the badging system uses notifications that interrupt
the task whenever a badge is awarded, and a student groans
and tries to quickly click out of the notification every time
it appears, this could be an indicator that the notification
system is invasive. A future study may wish to see if these
notifications are detrimental to the badging system’s
effectiveness. Participants may mention how much they
enjoyed or disliked a particular aspect of the badging
experience (e.g., “The badges were hideous. You should
really hire a graphic designer”). This provides a better
understanding of whether the results were due to the
inclusion/exclusion of badges, or due to some unconsidered
extraneous variable such as visual design.</p>
    </sec>
    <sec id="sec-15">
      <title>6.3 Temporal complexity</title>
      <p>The experimenter may also wish to examine badge access
patterns. This creates challenges in regards to time. What
is the appropriate duration in which to consider the earning
of badges, and what sort of longitudinal impact will the
acquisition of these badges have for participants? Further,
how will badges be made available to earners on a long
term basis? When badges can be viewed on demand,
differences in the number of times the badges were
accessed in a particular experimental session may be
indicative of engagement or interest. A user who exerts
additional effort to frequently view badges or a list of
possible badges that can be earned is probably more
interested in the system than a user who never or rarely
accesses the badges.</p>
      <p>In sum, researchers are still trying to understand how to
build better badges. An understanding of what factors are
important to their effectiveness and which areas of
complexity are most relevant to digital badging studies will
help to further this effort. Factors related to these areas of
complexity may arise unexpectedly during experimentation
and should be recorded.</p>
    </sec>
    <sec id="sec-16">
      <title>7. DATA ANALYSIS</title>
      <p>During data analysis, it is important to consider who
actually earned and did not earn each badge. If badges
could be earned multiple times, it is also important to
consider the number of times each badge was earned. By
doing this, the researcher can test for effects of the
inclusion, earning, or award of badges on an individual
level, identifying the impact of badges independently
instead of just observing the system which contains them.
These analyses could yield results that help badging system
designers understand which criteria are the most useful for
badges in their system.</p>
      <p>Also, simply having a badge available in a course is
unlikely to be sufficient as a manipulation if the badge is
never earned or seen. For example, consider the case of
hidden badges, or badges users do not know about until
they are earned. If these hidden badges are never earned,
they serve the same role as if they never existed; they are
invisible to the user. The fact that the badges technically
could have been earned are unlikely to have affected the
dependent variables. In other words, the relationships
between badges can be more complex than they seem at
first glance. Badge visibility should be considered
carefully during data analysis. At minimum, be sure to
make the distinction between:
•
•</p>
      <sec id="sec-16-1">
        <title>Badges that were available, but never seen Badges that were available, and were seen, but not earned</title>
      </sec>
      <sec id="sec-16-2">
        <title>Badges that were available, seen, and earned once</title>
        <p>Badges that were available, seen, and earned multiple
times
Breaking down the results in this manner will enable
formation of more specific conclusions regarding the data.</p>
      </sec>
    </sec>
    <sec id="sec-17">
      <title>8. CONCLUSION</title>
      <p>While general rules and strategies that pertain to
experimental design are often applicable to badging
experiments, badging presents some novel challenges that
require careful consideration. It is important to understand
these challenges because more research is needed in this
area. Badging research is still in its infancy, despite the
rapid growth it has recently experienced. Although recent
years have generated exciting insights and ideas about
digital badging, future research will continue to illustrate
the precise conditions in which digital badges thrive.
Sound research design will help us to design the
experiments that collect the empirical data that help us to
outline these conditions. Meticulous experimentation will
yield data that will inform practitioners and future
researchers alike, enabling higher quality research and
more effective badging implementations.</p>
    </sec>
  </body>
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