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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Identifying User eXperiencing factors along the development process: a case study</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Marco Winckler</string-name>
          <email>winckler@irit.fr</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Cédric Bach</string-name>
          <email>cedric.bach@irit.fr</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Regina Bernhaupt</string-name>
          <email>Regina.Bernhaupt@ruwido.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>ICS-IRIT</institution>
          ,
          <addr-line>Univ. Paul Sabatier, RUWIDO</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>ICS-IRIT</institution>
          ,
          <addr-line>Université Paul Sabatier</addr-line>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>ICS-IRIT</institution>
          ,
          <addr-line>Université Paul Sabatier</addr-line>
        </aff>
      </contrib-group>
      <abstract>
        <p>Currently there are many evaluation methods that can be used to assess the user interface at different phases of the development process. However, the comparison of results obtained from methods employed in early phases (e.g. requirement engineering) and late phases (e.g. user testing) of the development process it is not straightforward. This paper reports how we have treated this problem during the development process of a mobile application called Ubiloop aimed at supporting incident reporting in cities. For that purpose we have employed semi-directive requirement interviews, model-based task analysis, survey of existing systems and user testing with high fidelity prototypes. This paper describes how we have articulated the results obtained from these different methods. Our aim is to discuss how the triangulation of methods might provide insights about the identification of UX factors.</p>
      </abstract>
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  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Author Keywords
Incident reporting systems, UX factors, development process
ACM Classification Keywords
H.5.m. Information interfaces and presentation (e.g., HCI):
Miscellaneous.
1 INTRODUCTION
Incident reporting is a very well-known technique in
application domains such as air traffic management and
health, where specialized users are trained to provide
detailed information about problems. More recently, this
kind of technique has been used for crisis management such
as the hurricane Katrina [1]. Such self-applications are
aimed to be accessible by the general public with a
minimum or no training. In the context of the project
Ubiloop, we are investigating the use of mobile technology
for allowing citizens to report urban incidents in their
neighborhood that might affect the quality of their
environment. We consider urban incidents as any
(micro)events, perceived by a citizen, that might affect the
quality of his urban environment (e.g. hornet nest, potholes,
broken bench, tags,…). By reporting incidents, citizens can
improve the quality of life by influencing the quality of
their environment. Figure 1 illustrates the overall scenario
of our case study.</p>
      <p>Despite the fact that incident reporting systems using
mobile technology are becoming more common, little is
known about its actual use by the general population and
which factors affect the user experience when using such
system. In order to investigate which user experience
factors must be taken into account when designing the
interface of mobile application for incident reporting, we
have employed several evaluations methods (including
semi-directive requirement interviews, model-based task
analysis, survey of existing systems and user testing with
high fidelity prototypes) along the development process of
the application Ubiloop (developed in the context of the
eponym project). Hereafter we report how, using several
evaluation methods, it was possible to:</p>
      <p>Identify which (and in what extension) UX factors
affect mobile incident reporting systems;
Associate UX factors and artifacts that are aimed to
support the design and implementation of systems;
Determine how users value the incident reporting
systems (in terms of UX factors) in both early and late
phases of the development process.</p>
      <p>The first two sections of this papers provide an overview of
the development process (section 2) and the methods
employed (section 3) in the Ubiloop project. Then, at
section 4 we describe how we have articulated the results in
order to provide a bigger picture of UX factors and artifacts
used during the development process. Finally we discuss
the results and lessons learned.
2 OVERVIEW OF THE PROCESS
We have followed a user centered design approach. Our
first goal was to identify how user experience factors are
important to the users when they are performing tasks such
as reporting, monitoring and sharing with other citizen’s
information about urban incidents. We firstly address the
following dimensions: perceived quality of service,
awareness of perceived user involvement with reported
incidents, perceived effects of mobile technology for
reporting incidents, trust, privacy, perceived usefulness,
usability and satisfaction with incident reporting systems in
urban contexts. These dimensions are articulated around
four main research questions:
•</p>
      <p>How citizens perceive and describe urban incidents as
part of their quality of life?
How does the choice of communication to digitally
report incidents in a mobile context influence the
overall user experience? If so, what dimensions of user
experience are important for such an incident reporting
application?
How does social awareness affect the user experience
when interacting with incident reporting systems?
What contextual factors are important for incident
reporting and which interaction techniques better assist
user in reporting incidents?
•
•
•
These questions were investigated along the development
process by the means of different evaluation methods as
shown by Table 1.
Figure 2 shows the articulation between methods and
artifacts produced. Notice that the dashed arrows indicate
the relationships ensuring cross-consistency between
artifacts and results obtained from the methods employed.
Figure 2 Articulation between artifacts and methods employed.
Thick lines indicated artifacts produced; thinner lines indicate
input for the method; dashed lines are used to show compatibility
checking between artifacts.</p>
      <p>
        In more general terms, this design process started by (
        <xref ref-type="bibr" rid="ref1">1</xref>
        )
benchmarking existing applications in order to provide a
coverage of the application domain. From this step we have
extracted (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) generic and representative scenarios that were
used to organize an (2.1) interview with (18 potential)
future end-users of the Ubiloop application. These
requirement interviews allowed us to identify new scenarios
(some of them not covered by existing applications),
expectations (that we name here early requirements) and
(2.2) UX factors that are associated to the scenarios. By
(2.3) analyzing a set of 120 scenarios it was possible to
identify a task pattern that was then specified by using a
task-model notation. This (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) task model was used to check
the coherence of the design with respect to the previously
identified scenarios. Then, design options supported by the
task model were (
        <xref ref-type="bibr" rid="ref4">4</xref>
        ) (
        <xref ref-type="bibr" rid="ref5">5</xref>
        ) prototyped and subsequently tested
with end users. During (
        <xref ref-type="bibr" rid="ref6">6</xref>
        ) user testing, we have assessed
(
        <xref ref-type="bibr" rid="ref7">7</xref>
        ) UX factors that were then compared with those
collected earlier during the (2.2) interviews.
3 METHODS EMPLOYED AND MAIN FINDINGS
In this section presents the methods and key findings.
3.1 Survey of Existing Systems
In order to analyze the actual support provided by existing
applications, we conducted an analysis of existing services
for incident reporting in urban contexts. This study focused
on the front office (i.e. reporter tools). Applications for
incident reporting were first identified from the set of tools
ranked by Web search engines (i.e. google.com). Then,
only those that were available for remote testing were
selected for further analysis.
      </p>
      <p>Fifteen applications were selected covering international
reporting services. What we found to be specific for the
area of incident reporting is the broad diversity of features
for reporting urban incidents (more than 340). Nonetheless,
these incident reports seem to share similar characteristics
which can be used for helping users to locate on the user
interface the service that better suits to the type of incident
s/he wants to report in a given context of use. Despite the
fact that these applications address the same problem of
reporting incidents in urban context using mobile
technology, none of them was implemented following the
same scenario; which might be explained by cultural
difference that affect the user experience with this kind of
applications. For example, in some countries the identity of
the citizen reporting the incident is always mandatory
whilst in other countries it was mainly optional or only
requested in specific types of incidents (that could be
perceived as denunciation).</p>
      <p>From the analysis of existing systems we have extracted a
set of generic and representative scenarios that should be
supported by our application. We could not find in the
literature any work describing UX factors addressing this
specific application domain.
3.2 Semi-directive requirement interviews
In order to understand users expectations and requirements
for the future system, two series of semi-directed interviews
were conducted. The first one, called general interview,
focused on how users perceive their environment and how
they formulate general requirements for reporting incidents
using a smartphone. The second one, called scenario-based
interview was designed to investigate how users react to
different situations that would be subject of an incident
report. Each series of interviews involved nine participants.
During the general interview, participants were prompted to
report about: how they perceive places and their
environment; negative experiences in terms of
environmental quality; personal involvement with
problems; preferred system design; and dimensions they
think important.</p>
      <p>In the scenario-based interview, participants were
introduced to 7 scenarios (one at once, in random order)
and then asked to explain how they would envisage
reporting incidents using a smartphone. The scenarios
included to report a broken street lamp, a pothole, a missing
road sign, a bulky waste, a hornet nest, a tag/graffiti, and a
broken bench in a park. These incidents were selected from
the set of scenarios supported by existing applications.
Moreover, each scenario was designed to highlight a
specific point, for example: a broken lamp points out an
incident that is difficult to illustrate with a picture, whilst a
hornet nest focus on the perceived danger. Every interview
included a short questionnaire on demographics and
technology usage. All sessions were recorded and then
transcribed by a French native speaker. The transcriptions
were analyzed accordingly to the grounded theory approach
[3][6]. A corpus of 92 240 words was analyzed resulting in
11 classes/codes with 1125 segments of text. The coding
was supported by the MaxQDA 10 software [8].</p>
      <p>
        The interviews provided two key pieces of information: i)
scenarios for reporting incidents, which can be associated to
a task that must be supported by the system; and, ii)
qualitative attributes that could be interpreted as UX factors
associated to the given scenario. For an example, let assume
the following segment given by participant P2: “…Besides
going to report your [own] idea, you could ask if there are
other ideas [proposed by other]... [that are] close to your
home...” From this passage, the participant clearly states a
UX factor (stimulation as described by Hassenzahl [4]) that
could influence him to perform the task (report [an
incident]). These two requirements interviews provided
evidence for identifying the following UX dimensions:
visual &amp; aesthetic experience, emotions (related to negative
experience of the incident and positive experience to report
it – joy / pride), stimulation, identification (through their
personality, their own smartphone, their sensibility to
specific incidents), meaning and value, and social
relatedness/co-experience.
3.3 Model-Based Task Analysis
From the analysis of existing applications and interviews
we have identified 120 possible scenarios that could be
generalized as a user task pattern consisting of: (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) to detect
the incident, (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) to submit an incident report and (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) to
follow up on an incident report. This pattern was modeled
using the task notation HAMSTERS [6] which feature a
hierarchical graph decomposing complex tasks into more
simple ones as shown by Figure 4. Tasks are depicted
accordingly to the actors involved in the task execution (i.e.
user, system or both). It also integrates operators for
describing dependencies between tasks (i.e. order of
execution). As this task model does not impose any
particular design for the system it can accommodate all the
scenarios identified during the analysis of existing
applications. By modeling user tasks it was possible to
identify aspects such as optional/mandatory tasks associated
to incident reporting, inner dependencies between tasks, as
well as pre- and post-conditions associated to tasks
execution.
3.4 Prototyping
In previous work [2] we have found that information related
to incidents includes: what the incident is about, when it
occurs, where it is located, who identifies the incident and
the expected outcomes leading to its solution. These
dimensions include optional and mandatory elements that
characterize incidents. For example, the dimension what
can include a combination of either a textual description, a
picture of the incident, or just an indication of the incident
category. Based on these early findings and the generic task
model described above we developed a low-fidelity and
then a high-fidelity prototype (see Figure 3). The prototype
takes full benefits of currently embedded technology
available in smartphones such as video camera and global
positioning systems (GPS). GPS makes the user’s task of
locating incidents easier and photos attached to the
description of incidents provide contextual information and
in some situation might be used as evidence of its
occurrence.
      </p>
      <p>a)
b)
c)
The user interface of the Ubiloop prototype supports all the
user tasks previously identified. The prototype was also
designed to support the early requirements expressed by
users. Moreover, the prototype was designed to create a
positive user experience that could be also inferred from the
results of the semi-directive requirement interview. For
example, to enhance the UX factor experience we deploy
the prototype in a smartphone (whose technology is
perceived as a stimulation for using the application), we
include categories of incident (as users said they are more
likely to report an incident if they could see example of
categories on incidents) and allow users to see reported
incidents in the neighborhood (as suggested by the
participant 2, see section 3.2).
3.5 User testing
A user testing with high-fidelity prototype was designed to
explore how users report urban incidents with Ubiloop. The
study was held at the campus of the University of Toulouse
during the summer 2012. Thinking aloud protocol was used
during the experiment. Users were asked to wear glasses
embedding a video recording system, so that it was possible
to determine where they were looking at whilst using the
prototype. The recording apparatus also included a logging
system and a screen recorder embedded into the
smartphone.</p>
      <p>Users were trained during 5 minutes on how to report a
simple incident (i.e. a Broken street lamp) with a
smartphone embedding Ubiloop. Participants were then
asked to follow a predefined route in the campus and any
report incidents found in the way. The route was populated
with tags prompting users to report fake incidents that refer
to the scenarios presented in section 3.2. In addition to these
predefines tags, users were free to report any other incident
he could see in the campus (and the route had many real
incidents such as potholes, tags, public light open during
day…). In addition to these tasks users were asked to fill in
a demographic questionnaire, an AttrakDiff questionnaire
[5] and a debriefing interview.</p>
      <p>Nineteen participants, ranging from 21 to 52 years old, took
part in the experiment. All participants successfully
complete the tasks. The analysis of data concerning UX
factors took into account the answers provided by the
AttrakDiff questionnaire, the users tasks and the comments
provided by users whilst performing the tasks. Again user’s
comments were transcribed and analyzed accordingly to the
grounded theory approach. At this time the segments were
coded accordingly to the actual tasks performed by the
users during the experiment.</p>
      <p>One of the findings is that all UX factors previously
identified during the semi-directed requirement interviews
(see section 3.2), were reported again during the user
testing. Nonetheless, due to space reasons, we illustrate the
description of findings to two factors, stimulation and
identification to incident, that we have found out to be key
UX factors to engage the process of reporting (when user
decides to report the incident s/he identified in the
environment).:
•
•</p>
      <p>Stimulation was evaluated during the user testing
through a question of the post-test interview: “Did you
discover some incidents on the University campus that
you could report with the prototype?” This UX factor
can was also detected during thinking aloud technique
and the Attrakdiff questionnaire.</p>
      <p>Identification to incident was evaluated with another
question of the post-test interview: “Are the incidents
you declared during the experiment candidates to be
really reported by you to the Ubiloop service”?
Furthermore, the evaluation of Identification to incident
reveals that a strong proportion of UT participants declare
to be ready to report some of the mandatory incidents (90 %
for Broken bench and Hornet nest; 75% for the Broken
street lamp; and 45% for the Heap of rubble). And
individuals are mainly ready to declare the incidents they
spontaneously discover during the experiment (according
that the declaration is easy to perform and useful). In other
words, the applications seem to be able to increase both
Stimulation and Identification to incident.
4 TRIANGULATION OF METHODS
To answer the research questions on what user experience
(UX) dimension should be taken into account when
designing incident reporting systems for urban contexts; we
have triangulated the results of the three methods used in
this work, as follows:
•
•
•
•</p>
      <p>During semi-directive requirement interviews users
expressed requirements and expectation for reporting
incidents by the means of personal stories that were
interpreted as possible scenarios of use. These
scenarios were then used to revise our original task
model for incident reporting systems.</p>
      <p>By using a model-based task analysis, it was possible
to remove ambiguities present in the discourse of
participants and then to formalize users’ requirements.
Moreover, model-based task analysis provided an
accurate description of user tasks. This step is
extremely important for future development of incident
reporting systems. As described in [7], tasks models do
not only improve the understanding of user tasks but
they also can be used to assess if an incident reporting
system was effectively implemented to support the
specified set of user tasks.</p>
      <p>In order to make sure that tasks identified in the
semidirective requirement interviews and model-based tasks
analysis are representative we compare them with a
survey of existing systems. The results confirm that our
analysis is exhaustive because our task model covers
all tasks supported by surveyed systems and these
systems do not implement any task that is not described
in the task model.</p>
      <p>The analysis of transcripts of semi-directive
requirements interviews also supported the
identification of UX dimensions associated to user
•
scenarios. By combining UX dimensions and user
scenarios it was possible to extrapolate the results in a
single task model as shown by Figure 4 where user
tasks are decorated with UX dimension (e.g. [ID] for
identification] so that the above could be read as
follows: "I am passing by at this park every Sunday and this
bench has not been repaired for weeks [ID]. It is time now to
report that, so it will get fixed. It is not really a problem or
unsafe, but the bench is simply not usable in the current state
[MV]. [: detect/recognize the incident:]. It seems important
now to make sure that the appropriate person is informed
about that bench [CX], I think I should use the application to
report the incident, because I want to be a good citizen [ID].
I think it is a good idea to send them a photo so they can see
that the bench is really broken and that the wood has to be
replaced. And when they see the photo they see that it is
really there and so they will not need my contact information
to have a proof that the broken bench really exists. [MV]
[:describe the incident:]”. This example shows how user
tasks are interrelated to the UX dimensions.</p>
      <p>The prototypes were building accordingly to the task
models. Once implemented, the prototype was
crosschecked in order to make sure that it can effectively
support the scenarios early identified. Thus, every
presentation unit (ex. screens and widgets) can be
easily associated with an element of the task model. By
extrapolation with the results from requirement
interviews we could extrapolate a tuple consisting of
user interface elements + user tasks + UX factors.</p>
      <p>Figure 4 Generic task and most important UX dimensions for each sub-task.
• During user testing is was possible to identify UX
factors during the execution of the tasks with the
prototype. It is interesting to notice that the scenarios
supported by the prototype were the same used during
interviews so it was possible to correlate the results
found in early and later phases of the development
process. Thus, we have found that the UX factor
stimulation reported during interviews to the tasks to
find incidents occurred again when the users use the
prototype to complete the same task. This confirms the
•
•
value of early identification of UX factors with
requirement interviews. Moreover, when counting the
number of segments of user testing reporting the UX
factor stimulation, we have found that this factor is
more frequent and even distributed along tasks. We
also have compared the categories of incident reported
by users during the thinking aloud and during the
debriefing; we have found that the distributions of
incidents across categories are more important in the
requirement phase (72 citations/42 categories) than in
user testing (80 cites/19 categories). Indeed, during the
requirement interview participants had difficulties to
identify/remember urban incidents whilst during user
testing participants had more ease to identify incidents
along the route of the experiment.</p>
      <p>Before the participants of the requirements interviews
had strong difficulties to identify, remember or imagine
urban incidents. It’s not the case (or less the case) when
users can interact with the mobile application.</p>
      <p>Others examples come from the responses to the
posttest interview question about the Stimulation factor.
”I never thought to report this kind of incident [a public
garbage with a broken top] before [to use the application],
but that true this is would be quickly a serious problem of
squalor.”
”That’s funny because this application gives me the
opportunity to discover my own environment with a new
eye.”
5</p>
      <p>DISCUSSION AND LESSONS LEARNED
Unfortunately, we don’t have room for providing a
comprehensive description of the results collected by the
different methods. Nonetheless, the results given in this
paper illustrate that UX factors can be detected both in early
and later phases of the development process. Moreover, in
some extend, such results can be correlated.</p>
      <p>One of the challenges was to determine the importance of
UX factors when they are collected in different phases of
the development process. In the present work we have been
using a simple counting method (number of segments) and
distribution of UX factors across users’ tasks. Using this
simple method we found some differences that require
further analyses. Nonetheless, it prompts by a case where it
would be interesting to have quantitative metrics of UX for
comparing them.</p>
      <p>It is important to associate the identifying UX factors with
the artifacts used to the design. In our study, we have found
that scenarios and task models works as a lingua franca for
mapping user requirements and UX factors. However, it is
worthy to notice that this might be specific to a certain
types of interactive systems that can be successfully
described by tasks models. We can just wonder if this
approach could work in application domain such as game
where user activity is harder to represent by the means of
task models. Further work is required to determine if other
design artifacts and evaluation methods can also be used to
provide such as articulation.</p>
      <p>We have deliberated performing the user testing with
highfidelity prototypes. We have found in the requirement
interviews that the use of the device smartphone is per se a
stimulating element. For the purpose of the project, it was
more important to test the high-fidelity prototype in a
situation of mobility than a paper-based mockup. However
it would be interesting to assess the impact of mockups on
the identification of UX factors.</p>
      <p>Acknowledgement
This work is part of the Ubiloop project partly funded by
the European Union. Europe is moving in France
MidiPyrenees with the European Regional Development Fund
(ERDF). Genigraph and e-Citiz are partner of this work.</p>
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