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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Preliminary study on the smartphone zombie phenomenon by utilising a monitoring application</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Yukitoshi Kashimoto</string-name>
          <email>yu-kashimoto@kddi-research.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jaakko Hyry</string-name>
          <email>ja-hyry@kddi-research.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pasi Karppinen</string-name>
          <email>pasi.karppinen@oulu.fi</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Harri Oinas-Kukkonen</string-name>
          <email>harri.oinas-kukkonen@oulu.fi</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Masato Taya</string-name>
          <email>ma-taya@kddi-research.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Chihiro Ono</string-name>
          <email>ono@kddi-research.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>KDDI Research Inc.</institution>
          ,
          <addr-line>Fujimino</addr-line>
          ,
          <country country="JP">Japan</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Oulu</institution>
          ,
          <addr-line>Oulu</addr-line>
          ,
          <country country="FI">Finland</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Several studies exist on the dangers of using a smartphone while walking. Unfortunately, pedestrians often disregard the warnings either intentionally or by accident as their focus is on the phone and not fully on the surrounding environment or situation. In this paper, we present our preliminary work to study the correlation between smartphone zombie behaviour and individual's psychological features, to reduce walking use. At first, in order to collect smartphone zombie behaviour from actual users, we have developed a monitoring application for smartphones. We asked seven subjects to install this application and continue living their lives normally for 15 days. For collecting the psychological features, we asked them to answer a profiling questionnaire.</p>
      </abstract>
      <kwd-group>
        <kwd>Smartphone zombie</kwd>
        <kwd>Smartphone addiction</kwd>
        <kwd>Problematic smartphone usage</kwd>
        <kwd>Trans-Theoretical-Model</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The dangers related to being distracted while a smartphone during walking
exist. This behaviour is often called smartphone zombie or sometimes shortened
to smombie. The term can be understood broadly as zombie phone use can
refer to a person focusing on their phone in any situation, be it during a dinner
or while driving a car. In this study we focus only on the walking phone use.
Walking smartphone zombie users often disregard warnings related to distracted
use either by accident as their focus is concentrated on the phone, or by choice
as they might feel necessary to reply a message or want to watch a video. This
results in them not fully concentrating to the surrounding environment or
situation at hand properly. A study from Australia found that from 4129 pedestrians
observed crossing the street, on average 20% were using their phones and would
also have a bigger likelihood for critical events, such as crossing at the wrong
time or not checking both ways before crossing [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. The number of users is also
steadily growing as shown by the increase in smartphones prevalence numbers
from 2010 to 2019. In Norway and Romania the prevalence rose from 31% to
86% and 2% to 86% respectively [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ].
      </p>
      <p>
        In Tokyo, from 2010 to 2014, 152 were injured for smartphone zombie [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]
and between 2014 to 2018 this number rose to 201 individuals [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. A growing
number of studies are trying to understand the problematic phenomenon and
create solutions that would reduce walking use. Some cities are even trying to
accommodate phone users by creating separate walking lanes [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. In Japan, a
telecommunications service company created a screen blocker application3 that
forced users to stop using the smartphone while walking. However, as this feature
completely prevented any phone use, it saw very little use in the general public.
Using a smartphone is also often shown to be tied to some forms of addiction
and several new applications have been introduced which let users track and
reduce their own use. However, these applications are not designed especially for
reducing smartphone zombie behaviour, but instead for overuse of a smartphone
in general. They commonly use time limits, application blocking, self-assigned
use goals and use statistics of the phone, as presented in [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. Therefore, we
think looking into additional approaches for changing the underlying behaviour
of people are needed, as well as natural and e↵ective smartphone features that
assist an individual in breaking the walking phone use habits specifically.
      </p>
      <p>In this paper, we present our preliminary work to study the correlation
between smartphone zombie behaviour and psychological features, to achieve the
above-mentioned behavioural change. At first, in order to collect smartphone
zombie behaviour from actual users, we have developed a monitoring
application for smartphones. We have asked seven subjects to install this application
and spend their daily lives normally for 15 days. For collecting the psychological
features, we have asked them to answer a questionnaire.</p>
      <p>Our major contribution is that we propose suppressing smartphone zombie
behaviour by utilizing Persuasive Technology approach. Specifically, we collected
realistic data on smartphone zombie behaviour through our monitoring
application and compared it with the questionnaire data. Second, we looked into the
correlation between the psychological features: Stage in the
Trans-TheoreticalModel, Risk/Benefit of smartphone zombie, Dickman’s Impulsivity Inventory,
Self-ecacy, and Big Five scores, and smartphone zombie behaviour.
2
2.1</p>
    </sec>
    <sec id="sec-2">
      <title>Literature review</title>
      <sec id="sec-2-1">
        <title>Study on smartphone zombie</title>
        <p>
          Smartphone zombie behaviour has been recently gathered more focus but is
still an understudied area of research. A study on phone use while crossing the
street showed that it takes more time to cross if a phone is used and it also
shows more tendency to do unsafe behaviour such as not looking or crossing
at the wrong point. [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ]. The slower walk gait was also a result in a study by
[
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] in this pilot study. The e↵ect might be due to individuals focusing their
        </p>
        <sec id="sec-2-1-1">
          <title>3 https://www.au.com/mobile/service/aruki-sumaho/</title>
          <p>
            attention on their phones. The e↵ects on the cognitive load, gaze and general
awareness has been studied and showed that general awareness is reduced when
using a phone, and reading is more disruptive than texting [
            <xref ref-type="bibr" rid="ref12">12</xref>
            ]. The walking
phone use also was found to be due to people having a feeling of missing out of
their social interaction. This fear of missing out (FoMo) increased the likelihood
of smartphone zombie behaviour and results in similar dangerous behaviour as
shown in other studies. In addition, this behaviour true for both genders and
older or younger age groups when the social desirability score was the same, [
            <xref ref-type="bibr" rid="ref1">1</xref>
            ]
indicating that personality traits have a link in zombie behaviour. Some research
try to tackle the problem by o↵ering the smartphone zombie users with a
radarlike assistance to avoid collisions with other people or obstacles[
            <xref ref-type="bibr" rid="ref11">11</xref>
            ]. However,
we argue that it would be more beneficial to also focus on the phone user’s
behaviour, instead of trying to only alleviate the problematic behaviour be it
unintentional or intended.
2.2
          </p>
        </sec>
      </sec>
      <sec id="sec-2-2">
        <title>Study on smartphone addiction</title>
        <p>
          While smartphone zombie as a behavioural problem requires research, an
understanding the underlying problem is essential. The growth in smart device use and
the link to excessive and problematic use has been studied for years, but
common terms, criteria and unified terminology are needed so that cross-cultural
and comparative studies and be made. Phone use has steadily grown and
according to a recent EU study on 19 countries, around 80% of 9-16 years old use
the internet on their phones [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ]. In addition, the use of various smart devices
starts at an increasingly younger age, which might also develop into smartphone
addiction as the adolescents are more vulnerable for mental health issues [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ].
Often overuse related symptoms are anxiety, depression, stress and poor sleep.
Many studies have also looked into smartphone addiction in relation to DSM-5
criteria on substance and gambling [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ] perspective as similarities seem to occur
for both addictions. Compared to DSM-5, addicted smartphone users often use
their phones in 1) problematic or dangerous situations, 2) lose interest in other
social situations like family, 3) continue use even with negative e↵ects, 4) have
diculty in controlling or stopping use, 5) constant need to check the phone,
6)increase phone use to get satisfaction or relaxation, 7) urgency and need to
be always connected, responding immediately, and 8) anxiety if the phone is not
available [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]. However, as of now there is no clear consensus on the terms or on
the exact definition on what amounts to a person being addicted to their
smartphone and how the level of smartphone addiction can be e↵ectively measured.
It is likely that smartphone addiction and the use of a phone while walking is
somewhat connected. As stated above, the need to constantly be connected, the
need to check one’s phone, anxiety from non-use and the need to respond to
messages immediately, a↵ects a person’s ability to focus on their surroundings
e↵ectively while walking. In various studies personality and gender play a role on
what type of smartphone use occurs, and which types of personalities are more
vulnerable for smartphone addiction. In multiple studies [
          <xref ref-type="bibr" rid="ref18 ref3">3, 18</xref>
          ] For example,
females are more likely to focus on social networking applications and a need to
maintain or create new relationships and have a higher dependency and
problematic use levels than males. Phone use by males is more reflected in gaming
applications, voice and texting as well as having a tendency for using phones in
risky situations. The correlation between the smartphone zombie behaviour and
the psychological characteristics of phone users might shed more light on how
reduction in phone use can be achieved.
3
3.1
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Method</title>
      <sec id="sec-3-1">
        <title>Theoretical background and policy</title>
        <p>Since we are in the initial stage of the study, we selected two theoretical
frameworks for the experiments and investigate the correlation between the
smartzombie behaviour and the frameworks through a field study.</p>
        <p>
          Trans-Theoretical-Model: Trans-Theoretical-Model (TTM)[
          <xref ref-type="bibr" rid="ref17">17</xref>
          ] is where
individuals achieve a targeted behaviour change by progressing through several
stages: Pre-contemplation, Contemplation, Preparation, Action, and
Maintenance. As an example, a person might be considering quitting smoking but is
currently in the contemplation stage and not yet committed for the behaviour
change. TTM is frequently used in clinical therapy for habitual behaviours such
as quitting smoking or drinking. In this study, we assume that smartphone
zombie behaviour is also similar to these habitual behaviours. TTM also shows that
we need to select suitable intervention strategies for individuals in various stages
of change for a better likelihood of success. As a starting point for this study, we
focus on the subjects who are either in the Contemplation or in the Preparation
stages, because achieving change in their behaviours should be easier as they are
more willing participants.
        </p>
        <p>
          Pathway model of problematic mobile phone use: Bullieux et al. proposed
a framework to describe the correlation between the dysfunctional mobile phone
use and specificity of the factors based on the related studies[
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]. They claimed
that there are four pathways as follows: the impulsive pathway, the relationship
maintenance pathway, the extraversion pathway, and cyber addiction pathway, to
reach dysfunctional use1. Here, we measure the correlation between smartphone
zombie behaviour and psychological features based on this model.
3.2
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>The smartphone zombie behaviour monitoring application</title>
        <p>In order to collect realistic smartphone zombie behaviour, we developed a
monitoring application for smartphones. It collects smartphone’s operational data
while a user is walking, including the foreground application used and whether
the display is on or o↵. The application also collects activity recognition data
for the subject such as “walking”, “still” or “tilting”. The collected data is then
stored into cloud storage from Amazon Web Services.
In order to collect the psychological features of the subjects, we distributed a
questionnaire.</p>
        <p>In the smartphone use part, we collected data on which smartphones
functions did the subjects use in their daily lives, such as calling, web browsing,
messaging applications.</p>
        <p>In the TTM part, we inquired where in the TTM model stage would the
subject consider themselves to be in and excluded everyone who was not in
either the Contemplation or Preparation stages.</p>
        <p>The smartphone zombie behaviour part focused on collecting data on the
phone functions the subjects used while walking and the reasons why they used
those functions.</p>
        <p>In “Risk/Benefit of being a smartphone zombie” part, we collected subjects’
opinions towards smartphone zombie behaviour with 14 questions. Seven
questions were about the risks related to smartphone zombie, which corresponded to
“Negative A↵ect” in the “Problematic mobile phone use” model. The other seven
questions are about the benefits, which corresponded to the “Positive A↵ect” in
the same model.</p>
        <p>
          In the intervention part, we collected the subjects’ preferences for smartphone
applications which could encourage users to stop smartphone zombie behaviour.
We asked subject to choose three of their favourite and one least-favourite
intervention applications they would be willing to installs on their own smartphone.
Figure 2 shows the intervention applications shown in the questionnaire. Table 1
shows the description of each App. We have created the intervention applications
by a behaviour change support systems (BCSS) and persuasive systems design
(PSD) model with guides on how to change people’s attitudes or behaviour [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ].
        </p>
        <p>In the psychological measurement part, we collected the subject’s
psychological features with the following: Dickman’s Impulsivity Inventory, Self-ecacy,
and Big five scores. Dickman’s Impulsivity corresponds to “IMPULSIVITY” in
Fig. 1. Self-ecacy corresponds to “Poor self-esteem”. Big five scores correspond
to “Neuroticism” and “Extraversion”.
We conducted the data collection between 25.12.2019 – 24.01.2020. First, we
recruited subjects from Lancers4, which is a crowd sourcing service in Japan,
willing to install the smartphone monitoring application. Through the service,
we recruited seven subjects who used an Android smartphone. They were
requested to install the monitoring application and spend their daily lives
normally. This monitoring period lasted between 06.01.2020 – 17.01.2020. Starting
from 17.01.2020, we asked subjects to answer the questionnaire and the reply
deadline was 24.01.2020.</p>
        <p>Mail/Message
Internet
Take photo
SNS
Games
Movies
Map
Healthcare
News apps
Dysfunctional
Functional
Openness
Conscientious
Extraversion
Agreeableness
Neuroticism</p>
        <p>#</p>
        <p>Age</p>
        <p>Gender
App. ZZoommbbiiee fsreecqounedncaydaayday</p>
        <p>Frequency of zombie
When considering
quitting zombie
behaviour?
Functions
while walking
e
r
i
a
n
n
o
i
t
s
e
u
QRisk score</p>
        <p>Benefit score
Impulsivity
Self-esteem
Big Five
Preferred App.</p>
        <p>Not-pref. App.
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Results</title>
      <p>4 Lancers: https://www.lancers.jp/
.)20 17
in15
m
(
e10
m
ed 5
sU0</p>
      <p>Subject #3
9
6
3</p>
      <p>3
Camera Google Google LINE Archero</p>
      <p>Chrome Maps heros
ity”, “Self-esteem” or“Bigfive”. For the intervention methods, (b) Notification
silencer is mostly selected as preferred app., while (a) Screen blocker is selected
as the most unpopular intervention app.</p>
      <p>Figure 3 shows the top five functions and time while walking for each subject.
We extracted the functions and time while walking from the monitoring
application. In order to calculate the time, we first used walking time from Google
Activity Recognition and Screen On/O↵ recordings. Then, we calculated the time
of Google Activity Recognition output if “walk” and Screen On/O↵ recording
was “On”. Surprisingly, among most subjects there was a significant di↵erence
between the self-reported answers in the questionnaire and “Functions and time
while walking” measurements. For instance, Subject#1 answered that she does
not use Game applications while walking. However, the monitoring application
data showed that she used Pok´emon Go5, a location-based game, the most while
walking.
5
5.1</p>
    </sec>
    <sec id="sec-5">
      <title>Discussion</title>
      <sec id="sec-5-1">
        <title>Comparison between the app’s data and questionnaire</title>
        <p>The comparison between the app’s data and questionnaire results demonstrates
that there is a cognitive di↵erence between the two for some subjects.</p>
        <p>First di↵erence was the frequency of using smartphone while walking. The all
subjects use smartphones while walking more than three times a day. However,
the only Subject #3,4 answer correctly. From this di↵erence, we consider that
it is dicult to ask subjects to recall the frequency accurately with the current
questionnaire. For our preliminary nature of this field study, we would study the
correlation with more subjects.</p>
        <sec id="sec-5-1-1">
          <title>5 https://www.pokemongo.com/en-gb/</title>
          <p>
            The other one is the di↵erence between the realistic app use while walking
under the monitored data and those which subjects answered in the
questionnaire. This di↵erence illustrates that it is dicult for the subjects to recall the
exact app they use while walking, since they mistakenly recall using other apps.
Similar discrepancy between recorded and self-reported use times for subjects
has been shown to be problematic in other self-reported research results [
            <xref ref-type="bibr" rid="ref14 ref16 ref21">14, 21,
16</xref>
            ]. Users often over- or underestimate their own use, so caution in self-reporting
questionnaires is advised.
          </p>
          <p>From another point of view, this might give some hints towards suitable
behaviour change. Seeing the actual smartphone zombie time and related
applications name might e↵ectively reduce zombie behaviour. Specifically, subjects
#1,2,5 might recognize that they are using their phones more while walking than
they had conceived.
5.2</p>
        </sec>
      </sec>
      <sec id="sec-5-2">
        <title>Correlation between psychological features and zombie behaviour</title>
        <p>We discuss each subject for their psychological features with mapping them to
(i) Impulsivity , (ii) Relation maintenance, (iii) Extraversion, and (iv) Cyber
addiction in “Pathway model of problematic mobile phone use”.</p>
        <p>Subject #4 is considered to be an (i) Impulsivity user, since he has higher
dysfunctional impulsivity score and Poor self-esteem score. Subject #1 is
considered to be a (ii) Relation maintenance user, since she has a higher Neuroticism
score. In addition, she answered that she uses SNS functions to communicate
with others, so that she would not make them feel uncomfortable. Subject #5
is considered to be an (iii) Extraversion user, since she has the highest score in
Big Five’s Extraversion score.</p>
        <p>Subject #2 and #3 are dicult to clearly categorize to (i)–(iv), since they do
not have any significant scores. Subject #2 is considered to be a light smartphone
zombie user, since their “zombie seconds a day” is significantly smaller than
others. In addition, he stated willingness to quit zombie behaviour by answering
“Tomorrow” in the TTM question on “When quitting zombie?”. Therefore, his
behaviour fits for a person that is in the preparation stage of change. Subject
#3 might be considered to be a (iv) Cyber addiction user, since she answered
using game application while walking. However, the monitoring data indicated
that she only plays games just for three minutes while walking . If anything, she
utilizes the camera application more while walking, which is not her answer in
the questionnaire.</p>
        <p>For the intervention methods, we could not find any significant di↵erence
between the subjects. However, the questionnaire implies that the subjects who
play games while walking prefer to select (f) Gaming and (i) Competition SNS
intervention methods, so that they can stop smartphone zombie while playing
with others.</p>
        <p>On the other hand, the amount of data we have collected is not enough to
find further implications toward the target behaviour change. Therefore, we plan
to conduct an experiment with more subjects. In parallel, we plan to collect more
than 500 participants for an updated questionnaire study based on the current
study.</p>
      </sec>
    </sec>
  </body>
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