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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Bringing Digital Games to User Research and User Experience</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Lennart Nacke</string-name>
          <email>Lennart.Nacke@acm.org</email>
          <xref ref-type="aff" rid="aff5">5</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Alessandro Canossa</string-name>
          <email>alessandroc@ioi.dk</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jörg Niesenhaus</string-name>
          <email>joerg.niesenhaus@uni-due.de</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Kai Kuikkaniemi</string-name>
          <email>kai.kuikkaniemi@hiit.fi</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stephan Engl</string-name>
          <email>mail@stephanengl.com</email>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Thomas Immich</string-name>
          <email>thomas.immich@centigrade.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Centigrade GmbH</institution>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Helsinki Institute for Information</institution>
          ,
          <addr-line>Technology</addr-line>
          ,
          <country country="FI">Finland</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>IT University of Copenhagen</institution>
          ,
          <country country="DK">Denmark</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>University of DuisburgEssen</institution>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>University of Regensburg &amp;, SirValuse Consulting GmbH</institution>
        </aff>
        <aff id="aff5">
          <label>5</label>
          <institution>University of Saskatchewan</institution>
          ,
          <country country="CA">Canada</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>In recent years, the gaming industry has grown up and digital games have become more complex products. With this maturity comes an increasing need for formal playtesting methods from user research and scientific methods from academia. Employing user research methods in game development, especially combined qualitative (e.g., questionnaires, interviews) and quantitative (e.g., EEG, EMG, game metrics) methods lead to a better understanding of the relationship and interactions between players and games. This panel gathers game user research industry and academic experts for discussing current methodological advancements and future challenges in playtesting, usability, playability evaluation, and general game user research.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Entertainment</kwd>
        <kwd>user experience (UX)</kwd>
        <kwd>digital games</kwd>
        <kwd>game metrics</kwd>
        <kwd>playtesting</kwd>
        <kwd>user studies</kwd>
        <kwd>empirical methods</kwd>
      </kwd-group>
    </article-meta>
  </front>
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      <title>-</title>
      <p>INTRODUCTION
Digital games have grown to be among the favorite leisure
activities of billions of people around the world. Today,
digital gaming battles for a share of leisure time with other
traditional activities such as reading books, watching
movies, listening to music, surfing the internet or sports.
They attract billions of players on a regular basis online and
offline, generating huge revenues. For example, market and
sales statistics from the NPD group show an increasing,
almost exponential, trend in hardware, software and
accessories sales of digital gaming products in the past
decade (see Figure 1).</p>
      <p>However, digital games are not only a relevant from a
commercial perspective. They also impose new research
challenges to many scientific disciplines, new and old.</p>
      <p>LEAVE BLANK THE LAST 2.5 cm (1”) OF THE LEFT
COLUMN ON THE FIRST PAGE FOR THE</p>
      <p>COPYRIGHT NOTICE.</p>
      <p>
        With recent advancements in the field of human-computer
interaction [
        <xref ref-type="bibr" rid="ref12 ref16">12, 16</xref>
        ], new tools, techniques, and methods
become available for precisely measuring how people
interact with entertainment technology [
        <xref ref-type="bibr" rid="ref5 ref9">5, 9</xref>
        ]. With new
measurements of player-game interaction, we aim at
supporting the traditional game development process and
improve game design beyond regular entertainment
domains (e.g., games for alternative purposes, such as
education, simulation, and professional training).
Improving Digital Game Design
In the games industry, user testing and user-centered design
[
        <xref ref-type="bibr" rid="ref19 ref21">19, 21</xref>
        ] together with playability evaluations [
        <xref ref-type="bibr" rid="ref10 ref3">3, 10</xref>
        ] have
become more common for creating digital games [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
Digital games are more about creating experiences than
regular software. The full potential of digital gaming
unfolds in the interaction of digital entertainment systems
with human players. However, the experience of playing
games is often unique and individual, consisting of many
factors that are hard to assess or even measure.
      </p>
      <p>
        Most knowledge of game design has been created during
years of practice and is often based on personal experience
of the game designer, which commonly comes from
observing individual reactions to game mechanics.
However, since such individual game design knowledge
takes years to manufacture, faster insights into the complex
player behavior as a reaction to game mechanics are
desirable. Recent solutions have used logging of event data
[
        <xref ref-type="bibr" rid="ref16 ref9">9, 16</xref>
        ] together with subjective and objective player
responses to get a more complete image of gameplay
experience. In a similar vein, the modeling of player
behavior aims at finding optimal spots in the game and
level design [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
      </p>
      <p>
        PANEL FOCUS
Previous panels and workshops at international conferences
have explored user experience (UX) measurement in games
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] and evaluation of player experience in games [
        <xref ref-type="bibr" rid="ref15 ref17">15, 17</xref>
        ].
We aim at taking the discussion of user experience
evaluation in games a step further by discussing (1) what
the status quo of player experience measurement and game
user research is and (2) how novel measurements contribute
to designing better games. Of special interest are the
differences between traditional user research and emergent,
quantitative behavioral tracking systems, such as game
metrics or physiological recording (e.g.,
electroencephalography (EEG), electromyography (EMG)
or eye tracking). More specifically, the panel will discuss
the role of user research and user experience in games from
three specific angles, which cover the current
state-of-theart and emergent practices and are aligned with the
expertise of the panel participants.
      </p>
      <p>User Research and Digital Games
User-oriented research and testing is essential to a game
production, because the perceived quality of a game is
directly related to UX. Game user research focuses on
usability and user experience. Within the games industry a
focus has been on adapting methods from usability testing
to the specific context of games, while within academia the
majority of published research has focused on the
properties of UX – what it is, how to define it and how to
measure it. Only within the past few years has knowledge
from the industry been integrated into academia and vice
versa.</p>
      <p>
        Games are entertainment products that – in order to
produce a good user experience – require the interaction
between player and game to run smoothly and without
disturbances of the game interface or environment.
Therefore, user testing and user research is of vital
importance to game production quality. User testing games
can be a major challenge, because of the sheer amount of
variables impacting on player-game interaction, but also
because of the requirements for resources and expertise
involved in many user-oriented methods. Additionally,
many of the methods developed for the testing of
productivity applications do not apply directly to games,
because these need to do more than providing a piece of
software with a high degree of usability: Games need to be
entertaining. This requires the introduction of approaches
such as playability heuristics [
        <xref ref-type="bibr" rid="ref10 ref3">3, 10</xref>
        ], which go beyond
regular quality assurance and iterative game design.
Since user-oriented testing and research is becoming more
widespread in the industry [
        <xref ref-type="bibr" rid="ref19 ref21 ref26 ref8">8, 19, 21, 26</xref>
        ], knowledge about
how to address the challenges of user testing has gradually
been built. Testing methods developed specifically for
games such as playability heuristics [
        <xref ref-type="bibr" rid="ref10 ref3">3, 10</xref>
        ], RITE [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] and
specialized usability approaches [
        <xref ref-type="bibr" rid="ref12 ref6">6, 12</xref>
        ] are making inroads
towards establishing a framework of tools for user testing
in game production. Player experience research benefits
from this development as it is now possible to approach
scientific, empirical assessment of digital gameplay. By
combining insights gained from numerical recording of
parameters (physically from players as well as technically
within entertainment software) and approaches toward
qualitative assessments of experience (including behavioral
observations), it is gradually becoming possible to render a
high-resolution image of the complex interactions driving
gameplay and player experience. The knowledge
integration of player experience research and industry game
user research is a focus of the panel discussions.
Challenges of Modeling UX in Digital Games
Gameplay experience (GX) is different from UX. In a game
the focus is usually on recreational and not on functional
interaction. While desktop software is primarily created
with functionality in mind, digital games are created with
an enjoyable experience in mind, which can stimulate
cognitive and emotional processing [
        <xref ref-type="bibr" rid="ref19 ref8">8, 19</xref>
        ]. While game
design is not about usability per se, a digital game benefits
from adhering to the tenets of usability and usability
appears to be a good foundation for an enjoyable GX [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ].
The focus on the experience in the design and development
of digital games results in two specific challenges for the
design and user-oriented evaluation of digital games:
Complexity and abstraction. Game software and player
interface have to be optimized with GX in focus. Within a
game, tasks and goals cannot be optimized using classic
usability tests, since the difficulty or complexity of the task
may provide the necessary challenge to elicit a desirable
GX. Digital games are complex software with complex
controls and interaction opportunities. Thus, individual GX
is hard to predict. For modeling GX, we must abstract to
basic forms of interaction taking place between users and
the system.
      </p>
      <p>
        Time. The temporal dimension of GX is linked to
psychological experience concepts such as flow [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ],
immersion, or presence [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. The experience of players will
change as time progresses and their understanding of
interaction with the game increases. Fundamentally, time
influences learning, which is central to gaming. For
example, rewards in the game ensure continuous play if
they are well-balanced at the right stages of temporal and
individual progression in the game.
      </p>
      <p>We will discuss challenges of modeling time and
abstraction as part of gameplay experience. In addition, we
aim to gather a profound critique of this experience model
from the experts in the panel and the audience attending
this interactive session. The discussions under this topic
will provide fundamental theoretical inputs and critique for
modeling game experience.</p>
      <p>
        The Role of Quantitative Analysis in Player Research
Testing during and after game production has been
performed for decades but developers have commonly been
using informal methods. Recently, a variety of
methodologies have however been adapted from HCI to
assist with this process, for example different forms of
usability-testing [
        <xref ref-type="bibr" rid="ref20 ref4 ref8">4, 8, 20</xref>
        ].
      </p>
      <p>Traditional methods (e.g., audiovisual recording,
interviewing players about their experience, and how game
design affected it) come with a large set of limitations.
Audiovisual recording is time-consuming to analyze, with
everything having to be done by hand, and is limited in that
not every action of the player in the game world can be
tagged and measured. Post-game interviews or surveys
suffer from the problem that they are difficult to relate to
specific of design features. After a 50-minute play session a
player may be asked what they did during the session, but
their recall of the events of the game will be to greater or
lesser degree imprecise, and their memories already biased.
Using smaller in-game surveys in conjunction with limited
playtime intervals may alleviate some of these problems;
however, no golden rule has emerged yet (as to what time
intervals should be used).</p>
      <p>
        In contrast to traditional methods, novel measurements [
        <xref ref-type="bibr" rid="ref13 ref22">13,
22</xref>
        ], such as behavioral tracking systems pose
methodological and empirical challenges for user
researchers. Of special interest to us here are the
differences in traditional user research and modern
behavioral tracking systems, such as game metrics or
physiological recording (e.g., electroencephalography
(EEG), electromyography (EMG) or eye tracking). How
can we model emotions using physiologically recorded
data? Once we understand player emotions, how can we
use this knowledge to improve game design? What does
knowledge about players’ visual attention in a game
contribute to level design? What conclusion can we draw
from mental workload assessment during certain player
tasks? These are some of the topics that we will address
here.
      </p>
      <p>
        POTENTIAL FOR DISCUSSION &amp; EXPECTED INTEREST
Over the past decade, a steadily increasing degree of
research interest has been aimed at the emotional and
affective aspects of user experience that digital games
provide [
        <xref ref-type="bibr" rid="ref11 ref24 ref7">7, 11, 24</xref>
        ]. How games have been evaluated has
historically been an informal process, however this is
changing rapidly as the gaming industry has adapted
techniques and processes from HCI, notably usability and
UX, to evaluate games in production [
        <xref ref-type="bibr" rid="ref1 ref8">1, 8</xref>
        ]. In recent years,
it has been realized that traditional usability testing does
not suffice because its standard metrics (e.g., effectiveness
in task completion, error rates, efficiency) are not directly
applicable to all aspects of digital games [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. Additionally,
they do not provide enough information to evaluate UX,
which is crucial in game development [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. This has
prompted the development of new methods for evaluating
UX in games, adapted from traditional usability, as well as
supplementary development of methods based on
physiological measures and instrumentation (user behavior)
approaches [
        <xref ref-type="bibr" rid="ref16 ref25">16, 25</xref>
        ].
      </p>
      <p>UX is currently a debated topic in HCI-circles, and
computer games provide unique challenges for measuring
and evaluating UX. These factors alone provide a high
expected interest from HCI researchers and practitioners in
the panel. Add to this the size of the gaming industry and
the amount of research being carried out on games, the
panel topics should be of direct interest to many attendees.
Key Takeaways
We intend this panel to have key benefits for participants
from research and industry, while giving hands-on insights
into the exciting area of game user research.
•
•
•
•</p>
      <p>An understanding of the current and emerging methods
for user-research and UX evaluation in the digital games
application domain.</p>
      <p>An overview of the current status quo of know-ledge
about UX in games and of the unique challenges of UX
modeling in computer games.</p>
      <p>Insights into possibilities for merging traditional
qualitative with emergent quantitative measures of user
behavior and UX in digital games.</p>
      <p>How to utilize the results of game user research and
game UX evaluation for improving game design.
ACKNOWLEDGMENTS
We thank Anders Drachen, Regan Mandryk, Heather
Desurvire, Hannu Korhonen, Jan Fietz, Gareth White, and
Graham McAllister for comments, creative input, and
support during the writing process of a draft version of this
workshop proposal paper.</p>
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