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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Promoting green mobility through gamified transportation campaigns</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Simone Bassanelli</string-name>
          <email>sbassanelli@fbk.eu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Federica Gini</string-name>
          <email>federica.gini@unitn.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Antonio Bucchiarone</string-name>
          <email>bucchiarone@fbk.eu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Annapaola Marconi</string-name>
          <email>marconi@fbk.eu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Fondazione Bruno Kessler</institution>
          ,
          <addr-line>Via Sommarive 18, Trento, 38123</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Trento</institution>
          ,
          <addr-line>Address, Via Calepina 14, Trento, 38122</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <fpage>183</fpage>
      <lpage>193</lpage>
      <abstract>
        <p>This paper explores the impact of gamified campaigns within the AirBreak project on promoting sustainable urban mobility. Designed to induce lasting behavior change, the campaigns target diverse scenarios, including home-to-work, home-to-school, and leisure travel. The study assesses the overall effectiveness of these campaigns, analyzing changes in individual mobility choices and their contribution on reducing CO2 emissions. Additionally, the paper delves into the motivational aspects of the campaigns, identifying features that influenced participants towards sustainable mobility. Understanding these motivational factors provides insights into key elements driving positive behavioral changes. Moreover, the research investigates user characteristics influencing consistent engagement in sustainable mobility choices. This analysis enhances our understanding of the factors shaping participants' inclination towards adopting and sustaining eco-friendly travel practices. Grounded in theoretical foundations, the study details data collection and analysis methods, presenting findings that offer valuable perspectives for future interventions and policy considerations in the context of gamified sustainable transportation campaigns.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;gamification</kwd>
        <kwd>green mobility</kwd>
        <kwd>green transportation</kwd>
        <kwd>behavior change</kwd>
        <kwd>sustainability1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Mobility assumes a crucial role in contemporary urban
settings, shaping the way citizens engage with the city,
access essential services, and participate in urban life.
The effectiveness and organization of mobility, as
highlighted by Vesco et al. [1], significantly influence
citizens’ experiences within the city. In this dynamic
context, cities grapple with a formidable challenge.
Administrators must not only ensure citizens’ right to
mobility and seamless access to local services, but also
strive to minimize the economic, social, and
environmental costs associated with the mobility
system. Addressing this challenge necessitates a
comprehensive approach that efficiently leverages
existing mobility resources while integrating and
promoting new or emerging mobility services,
fostering an integrated, efficient, and sustainable
mobility ecosystem [2]. In pursuit of this objective,
cities are strategically planning and implementing
interventions across infrastructures, services, and
mobility policies. While these elements are pivotal in
advancing sustainability and integration in mobility, it
is crucial to recognize the equally significant
sociotechnical dimension of user acceptance and adoption
[
        <xref ref-type="bibr" rid="ref4">3, 4</xref>
        ]. Innovative policies, infrastructures, and services
run the risk of falling short if not complemented by
0000-0001-6061-8169 (S. Bassanelli); 0000-0003-3427-3747 (F.
Gini); 0000-0003-1154-1382 (A. Bucchiarone);
0000-0001-86997777 (A. Marconi)
© 2024 Copyright for this paper by its authors. The use permitted under
Creative Commons License Attribution 4.0 International (CC BY 4.0).
initiatives aimed at increasing citizens’ awareness and
involvement in the transformative process, influencing
their mobility habits in a gradual yet profound manner
[1].
      </p>
      <p>
        In many instances, citizens’ everyday mobility
decisions are shaped by ingrained habits and
influenced by inaccurate or outdated beliefs [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. It is
essential for citizens to be well-informed about the
mobility services available in their city and their actual
value, encompassing considerations such as time, cost,
and environmental impact. A heightened awareness is
necessary for individuals to recognize the
repercussions of their daily choices, including their
impact on traffic, greenhouse gas emissions, and social
costs [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. Crucially, citizens should perceive
themselves as integral to a community where their
collective daily choices play a pivotal role in advancing
city-level mobility strategic objectives [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. In essence,
individuals and communities must cultivate a sense of
responsibility, contributing to the development of a
new cultural paradigm for both urban and rural
mobility.
      </p>
      <p>
        In recent years, substantial efforts have focused on
utilizing interactive technologies to enhance citizen
awareness, promote active participation, and induce
behavior change toward a more sustainable lifestyle.
Gamification, identified as a persuasive technology
with significant potential [
        <xref ref-type="bibr" rid="ref8 ref9">8, 9</xref>
        ], is increasingly
recognized for its applicability in the mobility domain
[
        <xref ref-type="bibr" rid="ref10 ref11 ref12 ref13 ref14 ref15">10, 11, 12, 13, 14, 15</xref>
        ], as well as in various other
environmental sustainability domains [
        <xref ref-type="bibr" rid="ref16 ref17 ref18 ref19">16, 17, 18, 19</xref>
        ].
The core concept involves harnessing the motivational
and persuasive influence of games through the design
of systems that effectively utilize and integrate game
concepts and elements [
        <xref ref-type="bibr" rid="ref20 ref21">20, 21</xref>
        ]. Gamified systems
incentivize individuals to make specific decisions or
perform essential tasks, crucial for achieving valuable
objectives [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ]. This transformation occurs by
converting potentially unattractive actions into
enjoyable and rewarding experiences [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ].
      </p>
      <p>
        The development of urban mobility policies has
become crucial for governments and stakeholders
aiming to support sustainability goals [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. Research
indicates that active and sustainable mobility can play
a vital role in reducing greenhouse gas emissions [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ].
Despite the societal and individual advantages of
active mobility, there is a challenge in convincing
people to shift from car-centric lifestyles [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ].
Therefore, we implemented two gamified sustainable
mobility campaigns providing more incentives for
users to adopt environmentally sustainable methods
of travel.
      </p>
      <p>The two campaigns, incorporated within the
AIRBREAK project2, have been designed and implemented
across various contexts such as commuting between
home and work, home-to-school travel, leisure
activities, and free time mobility. The aim of this
initiative is not only to alter users’ mobility patterns
during the campaign but also to instill a lasting
behavior change.</p>
      <p>In this paper, we present an exhaustive description
of the AIR-BREAK project and the implemented
campaigns (Section 2). In Section 3, we present the
theory and hypotheses that guide this paper. In Section
4, we introduce the methods used for the
questionnaire creation and evaluation, data collection,
and statistical analysis. Then, in Sections 5 and 6, we
report and discuss the findings after the analysis. We
conclude the paper with the conclusions and future
works related to the AIR-BREAK project in Section 7.</p>
    </sec>
    <sec id="sec-2">
      <title>2. The AIR-BREAK Project</title>
      <p>The AIR-BREAK project is centered on the core
objective of informing and heightening citizens’
awareness about sustainable mobility services, with
the goal of fostering the adoption of eco-friendly travel
habits. In outlining the project’s scope, various
campaigns have been designed to address four key
objectives. Firstly, the project endeavors to actively
engage citizens, making them aware of both existing
and newly introduced mobility resources.
Simultaneously, efforts are directed towards elevating
their awareness regarding the significant impact their
daily mobility choices can have. The ultimate ambition
is to contribute to the establishment of a new cultural
norm for urban and rural mobility within the city
community. Building on this foundation, AIR-BREAK
seeks to instigate a voluntary travel behavior change.
This is achieved through a strategic blend of virtual
(game-based) and tangible incentives, leveraging
personalized cooperative and competitive game
mechanics. The goal is to encourage and sustain the
adoption of more sustainable mobility habits among
the populace. Moreover, AIR-BREAK focuses on
community building. By actively involving citizens in
AIR-BREAK initiatives and events, the project aims to
foster the creation of a local community of users.
Tailored behavioral change programs are deployed to
reach diverse user segments, including primary,
secondary, and high school students, as well as
employees. The intention is to create synergies with
other AIR-BREAK initiatives, promoting a
collaborative and supportive environment. Finally,
AIR-BREAK emphasizes the importance of producing
measurable outcomes. This entails evaluating the
project’s impact in terms of engagement, retention,
increased awareness, and behavioral change. The
insights gained from these measurable outcomes will
be instrumental in refining and optimizing subsequent
phases of the AIR-BREAK project, ensuring continuous
improvement based on real-world experiences.</p>
      <p>
        Within the framework of the AIR-BREAK project,
we have conceptualized and executed diverse
sustainable mobility campaigns focusing on distinct
mobility contexts, including home-to-work mobility,
home-to-school mobility, leisure, and free time mobility.
These initiatives cater to a range of end-user groups,
encompassing the general public, students, and
employees. The subsequent section provides a concise
overview of each of these planned actions. AIR-BREAK
mobility campaigns have been implemented through
the Play&amp;Go platform that supports the definition and
management of different types of sustainable mobility
campaigns, customizable with respect to mobility
objectives and target users. The customization of
campaigns can concern: the means of mobility to be
promoted, the travel validation criteria, the
competitive/cooperative game elements
implemented, and the real incentives provided by the
campaign [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ]. Users interact with the system through
the Play&amp;Go App (see Figure 1), which supports
various functionalities. In addition to player
registration, discovering and registering for active
campaigns, managing the player’s profile, and
inspecting campaign results, the app incorporates a
robust tracking system able to track single and
multimodal sustainable trips. This system collects
journey data to assign rewards, modify the game status
for players based on their activities, and calculate the
reduction in CO2 emissions associated with
sustainable transportation choices instead of car use.
The app employs a specific formula that considers the
kilometers traveled using different sustainable
transportation means available in various mobility
campaigns. Furthermore, users can access information
on weekly and global rewards, as well as the rules and
regulations of different campaigns and engage in filling
out questionnaires. This multifaceted approach
enhances user engagement, promotes sustainable
mobility practices, and contributes to both individual
rewards and environmental conservation efforts.
      </p>
      <sec id="sec-2-1">
        <title>2.1. Urban Mobility Campaign</title>
        <p>
          The Urban Mobility Campaign (UMC) is an initiative
encouraging citizens to actively embrace sustainable
transportation through gamification. Registration and
utilization of the Play&amp;Go app for tracking eco-friendly
trips are essential components of engagement. Central
to the gaming experience in the UMC are the
EcoLeaves Points. These points serve to keep the user
motivated [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ] and as a cornerstone for progression in
both weekly and global leaderboards [
          <xref ref-type="bibr" rid="ref28">28</xref>
          ], thereby
influencing the allocation of weekly and final prizes.
Earned for each tracked and validated sustainable trip,
the calculation hinges on factors such as the distance
covered and the sustainability of the chosen means of
transportation. The core mechanics of the game
revolve around trip tracking, wherein players specify
their mode of — be it walking, biking, public
transportation, or car-pooling. An automatic
validation process ensures the accuracy of each trip,
avoiding potential game abuse [
          <xref ref-type="bibr" rid="ref26">26</xref>
          ].
        </p>
        <p>
          A thoughtful design choice involves the
introduction of daily limits on tracked kilometers and
trips to prevent disproportionate and unnecessary use
of transportation means. This limitation ensures a
more equitable gaming experience for all participants,
narrowing the performance gap between top players
and others actively engaged in the campaign.
Furthermore, constraints tied to the validity of tracked
trips based on location — valid only if the origin or
destination falls within the specific territory — add an
additional layer of relevance and authenticity to the
gameplay. Beyond the core mechanics, players have
opportunities to earn bonus Eco-Leaves points. These
incentives include inviting friends to join the game,
achieving success in weekly challenges, and obtaining
special badges that come with associated Eco-Leaves
bonuses. Participants can meticulously monitor their
mobility history and achievements through
personalized profiles, which showcase a diverse array
of badges symbolizing accomplishments. These badges
range from achieving specific Eco-Leaves milestones
to showcasing preferences in transportation modes,
reinforcing the exploration of various mobility
alternatives [
          <xref ref-type="bibr" rid="ref29">29</xref>
          ].
        </p>
        <p>
          Distinguishing itself from a one-size-fits-all
approach, the UMC thrives on its highly personalized
weekly challenges. This personalization is achieved
through a Recommendation System, ensuring that
challenges are not only motivating but also realistic,
avoiding frustration stemming from unattainable
targets [
          <xref ref-type="bibr" rid="ref30">30</xref>
          ]. The game seamlessly integrates both
single-player and multiplayer challenges, catering to a
diverse range of player preferences. Single-player
challenges span various types, including
performancebased, repetitive behavior, surveys, and events, each
contributing to the player’s Eco-Leaves points. In
multiplayer challenges, players experience a sense of
community and relatedness. These challenges come in
cooperative, time-based competitive, and
performance-based competitive modes. Cooperative
challenges necessitate cumulative effort from
participants, fostering a collaborative spirit.
Meanwhile, competitive challenges introduce a
captivating dimension with fixed targets, time
constraints, and performance-based criteria.
        </p>
        <p>A pivotal aspect of the UMC is the continuous
evaluation of player performance through game levels.
Players progress through different levels such as Green
Lover, Green Warrior, and Green Guru based on the
total points they accumulate. Importantly, this system
ensures that certain features of the game become
available to players upon reaching specific levels,
adding an element of progression and achievement to
the gaming experience. The gameplay adopts a weekly
structure, fostering a sense of regularity and allowing
for the creation of weekly leaderboards. These
leaderboards, reflecting performance within a specific
time-frame, contribute to the excitement of weekly
prizes offered by local sponsors. Importantly, this
structure provides newcomers with a fair opportunity
to compete with seasoned players, leveling the playing
field and maintaining a vibrant gaming community. To
incentivize sustained participation, the UMC concludes
with final prizes awarded to top players on the global
leaderboard. Both weekly and final prizes are
generously offered by local associations and sponsors,
enhancing the overall appeal of the campaign.</p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. High School Challenge</title>
        <p>The High School Challenge (HSC) is a competition
designed for high school classes, with the goal of
encouraging sustainable and active commuting from
home to school. Participants utilize the Play&amp;Go
application to track their eco-friendly journeys. Each
student not only competes individually in the UMC but
also contributes to their class’s overall standing in the
inter-school competition. Attractive prizes await the
most active and sustainable classes. The class
registration process involves the following steps,
facilitated by a designated reference teacher:
1. Participants download the Play&amp;Go
application and register for the game.
2. The reference teacher, using an institutional
email account, communicates the group data
through the registration form.
3. Teams are formed to compete in the
competition’s rankings.</p>
        <p>Teams must comprise students from the same
class, with a minimum of 10 students per team or the
entire class for classes with fewer than 10 students.
Classes achieving at least 90% participation receive an
initial bonus of 300 Eco-Leaves points. Teachers
interested in joining can also be part of the class team,
with a limit of one team per teacher. Participants
continue to use the Play&amp;Go application to track their
sustainable journeys. Each participant not only
competes individually but also contributes to their
team’s performance in the inter-school competition. In
this competition, all Eco-Leaves points earned by team
members throughout the competition’s duration using
the Play&amp;Go App are considered. The team
accumulating the highest number of Eco-Leaves
points, calculated as the average value of its members,
emerges as the winner.</p>
        <p>Throughout the competition, the global
leaderboard of classes can be accessed via the Play&amp;Go
App and the AIR-BREAK website. Upon the
competition’s conclusion, the teams leading the HSC
Global Eco-Leaves Points Rankings will be awarded
collective prizes.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Theory and hypotheses</title>
      <p>
        Given the various gamified campaigns in the
AIRBREAK project, all aligned with a common theme, we
identified the need to develop a cross-sectional
questionnaire applicable across all campaigns that
incorporate game elements. From a long-term analysis
of previous campaigns [
        <xref ref-type="bibr" rid="ref31 ref32">31, 32</xref>
        ], we identified a
different interaction between factors in relation to the
nature of different rewards and game elements, and
specific correlations between some factors, such as
campaign appreciation and behavioral change.
Therefore, we decided to base the new questionnaire
on specific relationships. Then, we formulated three
research questions.
      </p>
      <p>RQ1. To what extent was the campaign effective in
enhancing participants’ sustainable choices in terms of
mobility?</p>
      <p>RQ2. Is the preference for specific features of the
campaign related to users’ motivation in making
sustainable choices in terms of mobility?</p>
      <p>RQ3.Are there any characteristics of the users that
make them more prone to appreciate the campaign?
3 The full questionnaire can be retrieved here:
https://osf.io/6mrga/?view_only=d9ecfb3b679e41ecbb0fde89404b
2e7b</p>
      <p>
        The first research question stems from the fact that
the use of a gameful system does not mean guaranteed
success [
        <xref ref-type="bibr" rid="ref20 ref33">20, 33</xref>
        ]. Then, it is crucial to report whether
the campaign was effective in enhancing participants’
sustainable choices in terms of mobility. The second
research question stems from the need to identify
whether specific elements could be useful in the
creation of future sustainable mobility campaigns. The
last research question is based on data in the literature
[
        <xref ref-type="bibr" rid="ref34 ref35 ref36">34, 35, 36</xref>
        ] suggesting that users’ demographic
characteristics can modulate their appreciation for
gameful systems.
      </p>
    </sec>
    <sec id="sec-4">
      <title>4. Methods</title>
      <sec id="sec-4-1">
        <title>4.1. Questionnaire development</title>
        <p>
          Two questionnaires were used to evaluate users’
appreciation for the campaign and behavioral change
in terms of sustainable mobility. The first
precampaign questionnaire consists of six categorical
items related to the background information on users’
preferences for means of transportation — including
bus, train, bike, walk, and car —, and one categorical
item for information about the app. The post-campaign
questionnaire repeats the same questions as the first
one, and then, for the core part, a model with five latent
and 13 manifest variables was formulated following
the results of previous campaign analyses [
          <xref ref-type="bibr" rid="ref31 ref32">31, 32</xref>
          ].
These items were collected using a 5-point Likert-scale
with a magnitude from 1 (Disagree) to 5 (Agree).
Lastly, three open questions collected detailed
information on appreciated and non-appreciated
elements of the campaign3. The theory of the core part
consisted of five core constructs: intrinsic motivation
(IM), extrinsic motivation (EM), behavior change (BC),
tool attractiveness (TA), and future behavior (FB), and
a single item for the evaluation of the Overall
appreciation (OA). Moreover, items related to the
appreciation of game elements (TA2 — [Specific game
element] made it enjoyable to participate in the
[campaign] initiative), and those related to behavior
change due to game elements (BC3 — [Specific game
element] prompted me to go more often by
environmentally friendly means) were repeated for
each game element entered into the campaign to
assess how much specific game elements contributed
to campaign appreciation and actual behavioral
change.
        </p>
      </sec>
      <sec id="sec-4-2">
        <title>4.2. UMC participation</title>
        <p>The UMC (introduced in Section 2.1), ran from April
17, 2023, to September 24, 2023. Ferrara citizens
tracked their sustainable movements through the
Play&amp;Go app, including cycling, walking, taking the
bus, train, or carpooling. Participants actively took
part in personalized mobility challenges, striving to
climb the rankings and win various weekly and final
prizes. The results of the campaign have been highly
encouraging in terms of participation. As depicted in
Figure 2, a total of 258 citizens joined the initiative,
with 55% being women and 45% men. In terms of age
distribution, participants between the ages of 35-50
accounted for 37.8%, while those in the 20-35 age
group constituted 17.07%. Individuals between the
ages of 50-70 comprised 43.9%, and those under 20
made up 1.22%. To provide us with detailed feedback
on their enjoyment and effectiveness in behavioral
change, the questionnaire was sent to participants at
the end of the campaign.</p>
      </sec>
      <sec id="sec-4-3">
        <title>4.3. HSC participation</title>
        <p>The HSC (introduced in Section 2.2) lasted from April
3 to June 4, 2023, and utilized the Play&amp;Go App.
Through this application, students and teachers
tracked their sustainable movements (cycling,
walking, bus, train, or carpooling), engaging in team
play, and climbing the rankings to win final prizes.</p>
        <p>Notably, the HSC featured 7 teams (see Figure 3),
with 5 teams composed of students and 2 teams
consisting of teachers, adding a collaborative
dimension to the challenge. The overarching goal of
the HSC was to promote sustainable commuting
between home and school, as well as during leisure
time, for all students aged 14 and above. This objective
was achieved through cooperative efforts within
classes and inter-class competition among high
schools. To provide us with detailed feedback on their
enjoyment and effectiveness in behavioral change, the
questionnaire was sent to participants at the end of the
campaign.</p>
      </sec>
      <sec id="sec-4-4">
        <title>4.4. Confirmatory factor analysis</title>
        <p>
          Before analyzing the data comprehensively, we
carefully checked the theoretical arrangement of the
items against the data obtained through a
confirmatory analysis, and then grouped the items
differently within the questionnaire. Confirmatory
factor analysis (CFA) is employed to assess and
potentially refine a predefined model depicting the
relationships between latent variables (factors) and
observable (or measured) variables. CFA falls under
the umbrella of Structural Equation Modeling (SEM), a
statistical method that amalgamates multivariate
techniques such as regression analysis and factor
analysis. SEM investigates the connections among
variables, encompassing both observable and latent
ones, within a model specified by the researcher based
on theoretical considerations and prior findings. The
model parameters are typically estimated using
techniques like maximum likelihood from the
covariance matrix of the observable variables [
          <xref ref-type="bibr" rid="ref37 ref38">37, 38</xref>
          ].
Statistical evaluation of model fit is often performed
using the chi-square ( ²) goodness-of-fit test.
Additionally, the Root Mean Square Error of
Approximation (RMSEA), derived from the  ² test,
provides a measure on an absolute scale, reflecting the
model’s fit to the data while considering factors such
as model size and sample size. In this study, RMSEA
values below 0.05, Comparative Fit Index (CFI) values
above 0.96, and Standardized Root Mean Square
Residual (SRMR) below 0.08 are considered indicative
of a satisfactory fit [
          <xref ref-type="bibr" rid="ref37 ref39 ref40">37, 39, 40</xref>
          ], indicating that there is
no need to arrange items and the structure differently.
        </p>
        <p>
          Lastly, many authors do not rely on the analysis of
 ² value and its significance, as it is highly subject to
sample size [
          <xref ref-type="bibr" rid="ref41">41</xref>
          ]. We therefore preferred to rely on the
ratio of chi-square to degrees of freedom (df). Values
less than 2 are often considered acceptable. MPLUS
(version 8.4)4 was used to run the CFA.
        </p>
      </sec>
      <sec id="sec-4-5">
        <title>4.5. Questionnaire analysis</title>
      </sec>
      <sec id="sec-4-6">
        <title>4.5.1. Participants</title>
        <p>We examined information gathered from 117
participants (female = 67, aged between 16 to 70 years
old), who actively participated in two campaigns: HSC
(N = 26) and UMC (N = 91), and completed the final
questionnaire through Google Form. Of the 117
participants who completed the final questionnaire, 74
(all from the UMC campaign) had also completed a
precampaign questionnaire.</p>
      </sec>
      <sec id="sec-4-7">
        <title>4.5.2. Analysis</title>
        <p>
          We proposed an analysis method for the
questionnaire. Not to weight the number of items
related to the number of game elements, any item
related to the appreciation of game elements was
averaged (TA2), as were those related to behavior
change due to game elements (BC3). In addition, as
defined in other scales, such as MEEGA+ [
          <xref ref-type="bibr" rid="ref42">42</xref>
          ], and SUS
[
          <xref ref-type="bibr" rid="ref43">43</xref>
          ], we identified a unique final value to provide a
holistic evaluation of the
campaign, defined as “total score”, ranging from 0 to 1,
based on the formula  ⁄5, where  represents the
mean of the answers calculated for each user. The
choice of this formula falls back on the fact that, thanks
to the 5-point Likert-type answers, it is possible to
obtain a score ranging from 0 to 1, making it feasible to
create a priori thresholds for campaign satisfaction,
and because a successful sustainable mobility
campaign assumes that game elements and the
platform have been implemented properly to support
behavioral change during the campaign, and in the
long term. Furthermore, these elements succeed in
motivating users who are driven by intrinsic or
extrinsic motivation equally. The choice of using a total
comprehensive score stems from the need for
unambiguous value to understand how successful
sustainable mobility campaigns have been perceived.
The questionnaire’s design allows for the evaluation of
how various game elements impact campaign
appreciation and user motivation. Additionally, it
facilitates the summary, on one hand, and comparison,
on the other, of the distinct campaigns within the
AIRBREAK projects. While a more in-depth analysis of
each individual campaign is planned for the future, this
paper concentrates on the overarching aspects shared
by both campaigns. To answer to RQ1, we evaluated
the effectiveness of the campaign by comparing
participants’ sustainability scores at the beginning and
at the end of the campaign through a Wilcoxon test for
paired samples. Sustainability scores were calculated
using the following formula:
(
+ 
+ 
)⁄4 + (7 −
        </p>
        <p>)
+ 
2
with bus, train, bike, walk, and car being participants’
answers to a 6-point Likert scale on their mobility
habits (1 = almost never, 6 = more than once a day).
We examined participants who completed both the
initial and final questionnaires to assess the
effectiveness of the platform and gain insights into
how users’ habits before using the app might impact
post-results. We ran a series of Spearman correlations
between EM, IM, the total score and (i)
presustainability scores, (ii) post-sustainability scores,
and (iii) ∆ scores, representing the difference between
pre and post campaign scores. Furthermore, a
Wilcoxon test was used to compare participants’
scores in the EM and IM constructs. To answer to RQ2,
we analyzed participants’ open-ended responses to
the question "What did you like the most about the
campaign?" we categorized them into two groups
based on their answers. Users’ answers were short and
referred to specific elements of the campaign (e.g.,
"rewards", "points", "the initiative", "the idea"). We
used a Mann-Whitney test to compare participants’
total scores. Then, we ran a rank-transformed ANOVA
to compare IM and EM scores based on the elements
users valued most. Finally, to answer to RQ3 a
ranktransformed ANOVA was used to explore whether
demographic characteristics, such as age and gender,
influenced users’ total scores.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Results</title>
      <sec id="sec-5-1">
        <title>5.1. Participation results</title>
        <p>During the UMC campaign, exploiting the Play&amp;Go app,
nearly 31,000 journeys have been recorded that
covered over 148,000 sustainable kilometers, with
over 95,000 by bike and almost 15,000 walking
(resulting in zero impact) (see Figure 4). The
experiment demonstrated the ability to sustain
citizens’ motivation in long-term campaigns, with
continuous and consistent participation over the
initiative’s duration of more than 5 months. Exploiting
the post-campaign survey and in particular, analyzing
items related to behavior change (items BC1 and BC2),
the results showcased the capacity to change players’
behaviors: 94% of players stated they felt motivated to
adopt more sustainable mobility habits. Specifically,
79% incorporated sustainable mobility habits into
their daily commutes, and 77% for leisure travel.
Finally, a significant outcome is the participants’
satisfaction, with 98% expressing a definite
willingness to participate in future editions (item FB2).
This initiative also led to the formation of a local
community of motivated and active users advocating
for more sustainable mobility.</p>
        <p>For what concerns the HSC campaign, more than
100 students and teachers have participated in the
HSC initiative, with over 3,000 tracked journeys, in
Play&amp;Go, covering more than 9,000 sustainable
kilometers (of which 27% were by bike and another
27% walking - zero impact), and nearly 2 tons of CO2
saved (see Figure 5). Analyzing the post-campaign
survey, the experiment has demonstrated the ability to
change players’ behaviors (items BC1 and BC2):
almost 70% of players claim to have adopted more
sustainable mobility habits in their home-school (or
home-work) commutes, while 75% have improved
their habits during leisure time. Finally, an important
result (item FB2) is the satisfaction of the participants
(70% express a desire to participate in future editions)
and the creation of a local community of motivated and
active users for more sustainable mobility.</p>
        <p>Figure 5: Use of different transportation means in
HSC.</p>
      </sec>
      <sec id="sec-5-2">
        <title>5.2. Questionnaire results</title>
        <p>
          The test statistics for this model were RMSEA = 0.039,
 ²/df = 1.176, CFI = 0.986, and SRMR = 0.050. These
results indicated that the model fit was good (Figure
6). The data also indicated significant relationships
between several latent factors, however, two
hypothesized relationships (IM-BC, and EM-TA) were
not significant, so they were not reported in the model
structure. See Table 1 for a comprehensive overview.
The results show that users’ behavior change can be
explained by extrinsic motivation, thus conveyed
primarily by the rewards, while tool and game
elements’ attractiveness seem to be explained by
intrinsic motivation. Interestingly, the future behavior
is explained by both users’ expressed behavior change
values and tool attractiveness. As hypothesized, tool
appreciation and behavioral change reports go hand in
hand. Lastly, the final score for the campaign’s overall
appreciation, related to the item "Participating in
[campaign] was enjoyable overall", is explained by the
interaction with tool attractiveness and future
behavior. Based on these data, we were able to proceed
with the inferential analysis without having to change
the theoretical structure of the questionnaire and
without removing/changing items.
appreciation for the project (N = 117, M = 0.797, SD =
0.147). As is often the case with questionnaire data
with Likert-type scales [
          <xref ref-type="bibr" rid="ref44">44</xref>
          ], no data were normally
distributed within the measured variables. First of all,
we were interested in understanding the increase in
participants’ sustainability choices in terms of
transportation, and how their old habits are related to
their final overall score, along with the five constructs
(RQ1). To achieve this, we included in the analysis
those participants who completed both the pre- and
post-campaign evaluations (N = 74, due to missing
answers in the pre-campaign evaluation. All 74
participants are from the UCM campaign). Given the
non-normal distribution of the data, non-parametric
tests were employed for the analysis (refer to the
supplementary material for normality analyses6). We
utilized a Wilcoxon test for paired samples to compare
sustainability scores based on participants’ habits in
terms of sustainable mobility before and after using
the application. The results revealed a significant
difference in participants’ sustainable habits before
and after using the application (W = 371.5, p-value &lt;
0.001). Additionally, a series of Spearman correlations
were conducted between EM, IM, and (i)
presustainability scores, (ii) post-sustainability scores,
and (iii) ∆ scores, representing the difference between
pre and post-sustainability scores. This aimed to
assess the relationship between intrinsic and extrinsic
motivation and participants’ eco-friendly habits. A
significant negative correlation was identified
between pre-scores and the extrinsic motivation (EM)
construct (Figure 7; S = 83142, p-value = 0.047,  =
0.231).
        </p>
        <p>Importantly, no correlation was found between
prescores and the overall score, suggesting that the
campaign’s appreciation is independent of
participants’ previous habits in sustainable
transportation. Finally, no correlations were observed
between the other constructs and (i) pre-scores, (ii)
post-scores, and (iii) ∆ scores. Then we confronted
participants’ scores in the extrinsic motivation (EM)
and intrinsic motivation (IM) constructs (N = 117).
Also, in this case, we had to opt for a non-parametric
test since data did not distribute normally. A Wilcoxon
test highlighted a significant difference between the
5 https://cran.r-project.org/bin/windows/base/
6 Supplementary material
two constructs, with IM being higher than EM (Figure
8; W = 539, p-value &lt; 0.001).</p>
        <p>To answer RQ2, we analyzed participants’
responses to the question "What did you like the most
about the campaign?" Forty-nine (49) participants did
not reply to the open question (or replied "all" or
"nothing"). Notably, a significant number of
participants emphasized the reward aspects (Reward
group, N = 27), while others expressed a preference for
the initiative’s underlying idea, such as promoting
sustainable mobility (Initiative group, N = 27). The
remaining 14 participants’ replies focused on other
elements, such as the competition, and traveling close
to nature. We sought to explore whether users’
preferences had any impact on their scores in the
overall score and the intrinsic motivation (IM) and
extrinsic motivation (EM) constructs. First, a
MannWhitney U test was employed to assess potential
differences in the overall score between the two
groups (initiative, reward). The results indicated no
significant difference in the overall score between the
two groups (W = 293, p-value = 0.219).
Subsequently, a rank-transformed ANOVA was
conducted (one factor between preference, 2 levels:
initiative, reward; one factor within subscale, 2 levels:
IM, EM). The results revealed a significant main effect
for the subscale factor (F1,104 = 9.792, p-value = 0.002),
while no significant main effect was observed for the
preference factor (F1,104 = 0.234, p-value = 0.630).
Tukey post-hoc test7 confirmed the difference
between EM and IM (IM M = 4.296, SD = 0.729; EM M =
3.454, SD = 1.381; t = -3.129, p-value = 0.0023).
Additionally, no significant interaction effect was
present (F1,104 = 0.014, p-value = 0.907). Finally, to
answer RQ3, we conducted a 2x4 rank-transformed
ANOVA to examine potential differences in overall
scores based on participants’ age and gender (2
between factors: age, 4 levels: "&lt;20", "20-35", "36-50",
"51-70"; gender, 2 levels: female, male). The results
revealed no significant main effect for both age and
gender (age: F3,109 = 2.149, p-value = 0.0982; gender:
F1,109 = 1.2246, p-value = 0.271), and no significant
interaction effect between the two (F3,109 = 1.790,
pvalue = 0.153) (Figure 9).
7 Emmeans library</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>6. Discussion</title>
      <p>
        The mobility campaigns involved a total of 362
participants, producing a collective 33,987 sustainable
trips, for a total of 157,928 sustainable Kms, and
reducing CO2 emissions for a total of 34,8t. Analyzing
the questionnaires administered at the beginning and
end of the AIR-BREAK campaign, we found an increase
in terms of eco-sustainability by participants. In fact,
users reported significantly higher sustainability
scores at the end of the campaign. Furthermore, we
found that in the total number of users who completed
the post campaign questionnaire, the construct of
intrinsic motivation significantly outperforms that of
extrinsic motivation. This indicates that (RQ1) the
AIRBREAK campaign is effective in promoting
ecosustainable behaviors and particularly incentivizing
people to use more sustainable means in their daily
travel. Overall, the results obtained seem to indicate a
balance of the two to produce both a behavioral change
and an appreciation of the application, resulting in a
consequent long-term behavioral change expressed by
the users and an overall appreciation of the campaign.
As noted in the literature [
        <xref ref-type="bibr" rid="ref20 ref21">20, 21</xref>
        ], not necessarily the
implementation of game design elements produces an
effective gameful system. In analyzing participants’
preferences toward the campaign elements, we
identified two prevalent groups: those who showed
particular interest in the rewards (virtual and
otherwise) related to the campaign, and those who
liked the idea related to the initiative the most (RQ2).
Despite the division into the two groups, the data
showed no differences in the total score, as well as
indicating that in both cases IM is higher than EM. This
suggests that the design of the gameful system does
not make participants overly attached to rewards. Due
to the lack of a main effect of the group, as well as the
absence of an interaction effect between the two
factors analyzed, we can not identify specific elements
in the campaign that motivated users more than others
in adopting sustainable mobility behaviors. In
addition, we found no differences in campaign
appreciation (total score) by age and gender of
participants, indicating how the initiative is
appreciated by different demographic groups (RQ3).
As noted in the literature, it is possible that age and
gender moderate the appreciation for different aspects
of the gameful design [
        <xref ref-type="bibr" rid="ref34 ref35">35, 34</xref>
        ]. The absence of
differences in appreciation of the initiative’s design
and gamified system is an excellent finding, given that
the campaign aims to raise awareness of sustainability
with a broad demographic. We did find, however, how
EM correlates negatively with sustainability score at
the beginning of the campaign. This suggests that the
presence of game elements may indeed capture the
attention of those who were not particularly inclined
to use environmentally sustainable means of
transportation. It also suggests that they do not lead to
phenomena such as the over justification effect [
        <xref ref-type="bibr" rid="ref45 ref46">45,
46</xref>
        ] in those users who were already showing high
levels of sustainability instead.
      </p>
      <sec id="sec-6-1">
        <title>6.1. Limitations</title>
        <p>
          It is necessary to point out that the reported results
have limitations. First of all, data in the literature
report that for factor analyses, a size larger than 200
participants is recommended [
          <xref ref-type="bibr" rid="ref47">47</xref>
          ]. Furthermore, the
sample size was found to be non-homogeneous
between different analyses. Unfortunately, not all
users responded to either the pre- or post-campaign
questionnaire, leading to varying sample sizes based
on the analysis conducted. Regarding pre-post analysis
in campaigns, it should be noted that few users
responded to the pre-campaign questionnaire,
reducing the reliability of this data. Although there is
data on CO2 savings produced, behavioral change and
future behavior are inferred from items and not from
behavioral analysis, hence it is not possible to clearly
and linearly determine whether users were moving
sustainably even before the campaign.
        </p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>7. Conclusions and future works</title>
      <p>In this paper, we introduced AIR-BREAK, a project
designed to promote sustainable behaviors within the
general population, with a particular focus on
encouraging eco-sustainable mobility practices.
AIRBREAK has exhibited considerable success in
facilitating a positive shift towards more sustainable
daily travel methods. The mobility campaigns
developed and implemented in this project garnered
significant participation, resulting in a noteworthy
increase in sustainable trips, and a reduction in CO2
emissions. The findings indicate that the gamified
approach, incorporating intrinsic motivation and tool
attractiveness, has proven effective in motivating
individuals to embrace and maintain environmentally
friendly transportation choices. The questionnaire
analyses revealed an overall improvement in
participants’ eco-sustainability scores. Notably, the
campaign’s effectiveness transcends demographic
characteristics such as gender and age, indicating its
broad appeal and impact. It’s worth mentioning that
while a significant number of participants identified
rewards as a positive aspect of the campaign, this did
not compromise their intrinsic motivation. In
summary, the AIR-BREAK project has not only
successfully met its initial goals of encouraging
sustainable mobility throughout the campaign but has
also established the groundwork for enduring
behavioral transformations. The emergence of local
communities championing sustainable mobility and
the highly positive feedback from participants suggest
the project’s potential for a more extensive societal
influence. As urban centers persist in addressing the
complexities of mobility, the AIR-BREAK project offers
valuable lessons on the efficacy of gamified
interventions in fostering environmentally conscious
behaviors, opening avenues for future innovations in
sustainable urban mobility initiatives.</p>
      <sec id="sec-7-1">
        <title>7.1. Lesson learned</title>
        <p>The insights gained from the AIR-BREAK campaign
provide a foundation for future initiatives aiming to
promote sustainable behaviors. Moving forward, the
positive correlation between intrinsic motivation and
sustainability scores suggests a focus on designing
gamified systems that tap into users’ inherent
motivations. Furthermore, understanding the diverse
preferences of participants — some favoring rewards
while others valuing the initiative itself — indicates
the potential for tailored campaign elements to engage
a broader audience. To leverage these findings, future
campaigns could implement adaptive gamification
strategies, tailoring elements to individual preferences
to maximize engagement. Additionally, considering
the lack of significant differences in campaign
appreciation based on age and gender, future
initiatives might adopt inclusive design principles,
ensuring accessibility and appeal across diverse
demographic groups. Addressing limitations, future
campaigns could strive for larger and more
homogeneous sample sizes, employing robust
methodologies for pre-post analyses. The integration
of behavioral analysis alongside self-reported data
could provide a more comprehensive understanding of
the sustained impact of gamified interventions on
participants’ mobility choices.</p>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>Acknowledgements</title>
      <p>This work is supported by the AIR-BREAK project
funded through the ERDF Urban Innovation Actions
2020 UIA 05-177. We also acknowledge the support of
the PNRR ICSC National Research Centre for High
Performance Computing, Big Data and Quantum
Computing (CN00000013), under the NRRP MUR
program funded by the NextGenerationEU.</p>
    </sec>
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