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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Towards Estimating Happiness using Social Sensing: Perspectives on Organizational Social Network Analysis</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Martin Atzmueller</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Daan Kolkman</string-name>
          <email>d.a.kolkman@uvt.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Werner Liebregts</string-name>
          <email>w.j.liebregts@uvt.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Arjan Haring</string-name>
          <email>a.haring@jads.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Jheronimus Academy of Data Science (JADS)</institution>
          ,
          <addr-line>Sint Janssingel 92, 5211 DA 's-Hertogenbosch</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Tilburg University, Department of Cognitive Science and Artificial Intelligence (CSAI)</institution>
          ,
          <addr-line>Warandelaan 2, 5037 AB Tilburg</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Tilburg University, Tilburg Institute of Governance (TIG), Tilburg School of Economics and Management (TiSEM)</institution>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Social sensing provides many opportunities for observing human behavior utilizing objective (sensor) measurements. This paper describes an approach for analyzing organizational social networks capturing face-to-face contacts between individuals. Furthermore, we outline perspectives and scenarios for an extended analysis in order to estimate happiness in the context of organizational social networks.</p>
      </abstract>
      <kwd-group>
        <kwd>social sensing</kwd>
        <kwd>social network analysis</kwd>
        <kwd>happiness</kwd>
        <kwd>organizational networks</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        With the emergence of the Internet of Things (IoT), smart devices, and ubiquitous
computing, social sensing enables the collection of multi-modal interaction data at an
unprecedented scale. Social sensing methods have been applied in diverse domains,
e. g., [
        <xref ref-type="bibr" rid="ref1 ref12 ref24 ref30 ref39 ref41 ref42 ref51 ref9">1, 9, 12, 24, 30, 39, 41, 42, 51</xref>
        ]). Their insights enable the understanding of human
behavior, as well as to enable structural modeling and the analysis of social interaction
structures. Specifically, social networks in the context of organizations capture
individual behavior as well as group-behavioral patterns. Then, these can be used for
potentially estimating both individual and collective happiness, also relating to well-being.
      </p>
      <p>This paper discusses perspectives on the analysis of complex organizational
networks as well as estimating happiness using social sensing. Furthermore, we describe
a computational social sensing method using wearable sensors combined with first
results on analyzing organizational social networks. After that, we provide an outlook on
how to estimate happiness in two organizational social network settings, i. e., in student
groups as well as in groups involved in startups.</p>
      <p>The remainder of the paper is structured as follows: Section 2 discusses related
work. After that, Section 3 presents a conceptual overview on the concept of happiness
and its possible estimation. Section 4 outlines the social sensing method and discusses
first results. Section 5 discusses according social network analysis methods and a
social sensing framework for estimating happiness. Finally, Section 6 concludes with a
summary and outlines opportunities for future work.</p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>This section first discusses related work on social network analysis and social sensing,
before we focus on conceptual approaches for estimating happiness in the next section.
2.1</p>
      <sec id="sec-2-1">
        <title>Analysis of Social Interaction Networks and Group Behavior</title>
        <p>
          The analysis of interaction and groups, and their evolution, respectively, are prominent
topics in the social sciences, e. g., [
          <xref ref-type="bibr" rid="ref20 ref34 ref55 ref57">20, 34, 55, 57</xref>
          ]. Wasserman and Faust [
          <xref ref-type="bibr" rid="ref59">59</xref>
          ] discuss
social network analysis in depth, and provide an overview on the analysis of cohesive
subgroups in graphs. Arrow et al. [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] specifically focus on the behavior of small groups.
First analyses concerning group contact evolution have been reported in [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ], where the
temporal evolution of smaller groups (up to size four) were analyzed. Brodka et al. [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ]
investigate group formation and group evolution discovery in social networks.
        </p>
        <p>
          This paper considers social interaction networks of face-to-face contacts captured
using social sensing as outlined below. We focus on analyzing dynamic contact and
group behavior in a social network analysis and mining setting, e. g., [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ]. Furthermore,
we focus on indicators regarding “social event happiness” given the contact dynamics.
2.2
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>Social Sensing</title>
        <p>
          The analysis of human contact patterns and their underlying structure is an interesting
and challenging task. An analysis, e. g., using proximity information collected by
bluetooth devices as a proxy for human proximity is presented in [
          <xref ref-type="bibr" rid="ref23">23</xref>
          ]. However, given the
range of interaction of bluetooth devices, the detected proximity does not necessarily
correspond to face-to-face contacts [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ].
        </p>
        <p>
          The SocioPatterns collaboration developed an infrastructure that detects close-range
and face-to-face proximity (1-1.5 meters) of individuals wearing proximity tags with
a temporal resolution of 20 seconds [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ].4 This infrastructure has been deployed in
various environments for studying the dynamics of human contacts, e. g., at
conferences [
          <xref ref-type="bibr" rid="ref19 ref40">19, 40</xref>
          ]. They presented an application that combines online and offline data
from conference attendees [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ], similar to the Conferator [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ] system. The
SocioPatterns (hardware) framework provides also the technical basis of the Ubicon software
platform [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ]5 for observing social and physical activities, such as (social) interactions
but also relating to spatio-temporal processes [
          <xref ref-type="bibr" rid="ref53">53</xref>
          ]. In this context, Atzmueller et al. [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ]
analyze the interactions and dynamics of the behavior of participants at conferences;
similarly, the connection between research interests, roles and academic jobs of
conference attendees is further analyzed in [
          <xref ref-type="bibr" rid="ref40">40</xref>
          ]. Another approach for observing human
face-to-face proximity and communication is the Sociometric Badge [
          <xref ref-type="bibr" rid="ref60">60</xref>
          ].6 It records
more details of the social interaction, but requires significantly larger devices.
        </p>
        <p>
          In this paper, we outline an exemplary study with first results, where we utilize the
Sociopattern proximity tags and the Ubicon platform [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] for observing physical
(faceto-face) interactions, towards objectively estimating happiness indicators.
4 http://www.sociopatterns.org
5 http://www.ubicon.eu
6 http://hd.media.mit.edu/badges
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Happiness – An Conceptual Overview</title>
      <p>
        In recent years, we have seen a sharp increase in publications on the “science of
happiness”, and a concomitant rise in the public interest for such studies. The underlying
rationale of such works suggests that the scientific method can be applied to measure,
study, and better understand happiness. Since our methods have improved, some believe
conventional ways of measuring well-being and happiness are no longer elusive [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
This renewed academic as well as popular interest has had a considerable impact;
increasingly, well-being and happiness are framed as a skill that can be learned. Not
surprisingly, an industry consisting of motivational speakers, self-help books, and other
personal development professionals now aim to assist in our pursuit of happiness [
        <xref ref-type="bibr" rid="ref31">31</xref>
        ].
      </p>
      <p>
        Traditionally, happiness is conceptualized as the subjective part of the concept of
well-being. Bartram explains that a distinction can be made between objective
wellbeing and subjective well-being [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. The first can be readily conceptualized and
measured; it includes, amongst other things, income and access to goods. The latter,
however, is entwined with experiences and emotions and therefore often harder to
determine. That is, emotions are harder to observe in other people, as most people would only
be able to state whether they themselves are happy or not. Subjective well-being can be
divided into two components: (1) Happiness, the affective component, and (2) life
satisfaction, a cognitive component that covers our self-evaluations about how well we feel
our lives are going. While – or perhaps because – the concept of happiness is relatable
for anyone, there is no shortage of definitions in the literature. Examples include
“feeling good” [
        <xref ref-type="bibr" rid="ref36">36</xref>
        ], “a positive emotional state” [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ] and a “whimsical state of mind” [
        <xref ref-type="bibr" rid="ref58">58</xref>
        ].
The common process of developing a sound measure of happiness requires researchers
to make arbitrary judgments about what questions to include, to whom to ask them,
and what phrasing to use. Moreover, subsequently adjusting the measurements through
statistical analysis requires further normative judgment from the researcher [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        Most (conventional) research on happiness employs surveys that ask participants to
score their happiness on Likert scales. Other forms of data on happiness include
“experience sampling”, which is a diary method that asks participants to score and record their
happiness several times a day [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. A related body of research has considered a wealth
of determinants and correlates of happiness. One of the most researched areas includes
correlations between income and happiness, an area influenced by studies in behavioral
economic [
        <xref ref-type="bibr" rid="ref31">31</xref>
        ], e. g., that those with higher incomes are happier than those with lower
incomes, but an increase in one’s income generally does not lead to an increase in
happiness [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ]. Rather, some would suggest that society’s increase in wealth has gone hand
in hand with greater levels of distress [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. However, there are good reasons to question
the applicability of the current scientific method to the study of happiness. First,
scientists are not the only authority on norms. Given that we are all familiar with making
judgments on “what makes us happy”, it seems problematic to grant academia a
privileged position to determine what is – or is not – covered by the concept [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Second, we
can consider how happiness is typically measured. Most of the previous contributions
use surveys, or rely on self-report diaries to score happiness. Both methods require
considerable effort from participants and can suffer from decreasing completion rates and
hindsight bias. This paper contributes to the second challenge aiming at the
development of a new approach for estimating happiness using wearable sensors.
      </p>
    </sec>
    <sec id="sec-4">
      <title>Method</title>
      <p>This section discusses perspectives on estimating happiness using social sensing. For
that, we sketch a method for social sensing using wearable sensors that capture
faceto-face interactions between participants. In particular, this is targeted at observing
interactions in social groups. We exemplify the method using an analysis in the context
of the career perspective day 2017 at the Jheronimus Academy of Data Science. Here,
we discuss preliminary results as well as first directions towards the formalization of
happiness indicators regarding (social) groups, e. g., in educational settings.
4.1</p>
      <sec id="sec-4-1">
        <title>Observing Interactions in Social Groups using Wearable Sensors</title>
        <p>
          The estimation of happiness in educational groups, e. g., student groups is relevant,
since there is a link between academic achievement and happiness, e. g., [
          <xref ref-type="bibr" rid="ref16 ref29 ref50">16, 29, 50</xref>
          ].
As a first preliminary experiment for estimating happiness, we applied wearable
sensors at a career perspective data, observing face-to-face contacts between participants
(students) and companies. The context of the experiment was given by the JADS
Career Perspective Day. It aimed at attracting student participants who were considering
a career in the world of data science, i. e., in order to inform about expectations about
working as data scientist, how businesses are applying data science, to get insights into
personal career opportunities, and – in particular – to meet companies. At the JADS
Career Perspective Day on May 19th, 2017, we offered wearable sensors (Sociopatterns
proximity tags) to the students. In addition, we tagged stands of companies in order to
estimate the contacts between participants and companies. In that way, we could extract
a bi-modal network of participant-company interactions. We sketch first findings below.
        </p>
        <p>
          Similar to the scenario of student groups, happiness can also be estimated in the
context of startups (i. e., entrepreneurial happiness). This is relevant because there is
evidence of a link between productivity and happiness, cf., [
          <xref ref-type="bibr" rid="ref46 ref47 ref48">46–48</xref>
          ]. Also, we believe
that there might be a link between happiness and other relevant factors, like creativity
and focus, which we also aim to examine in further experiments.
4.2
        </p>
      </sec>
      <sec id="sec-4-2">
        <title>First Results</title>
        <p>
          As outlined above, proximity tags were offered to participants. In total, 118 participants
volunteered to take part in the experiment.7 Furthermore, 35 tags were used for tagging
company stands. Figure 1 shows the respective degree distributions of participants and
company stands, respectively. These indicate the “contact distributions” with respect to
unique contacts to participants and company stands, respectively. Overall, we can see
that the participant degree distribution is left-shifted (towards a heavy-tailed
distribution), while the stand degree distribution has a more gaussian-like distribution. From
both, we could model indicators about “event happiness” regarding the expectations of
companies and participants, based on statistical measures like the corresponding nodes’
degree compared to the mean degree of the nodes in the network, similar to
distributional analyses as a proxy for social phenomena [
          <xref ref-type="bibr" rid="ref44 ref45">44, 45</xref>
          ]. These can be validated using
surveys, by comparison to the overall distribution, or using appropriate null-models.
7 Study participants also gave their informed consent for the use of their data in scientific studies.
0
2
5
1
5
ycne
u
reqF 01
        </p>
        <p>Contacts/Stands/Participants
5
1
5
cy 10
n
e
u
q
e
r</p>
        <p>F
0</p>
        <p>0
0
5
15
20
0
10
20
50
60
70
10
Degree
30</p>
        <p>
          40
Degree
This section first discusses social network analysis and its implications towards
estimating happiness. After that, we sketch a framework towards measuring happiness using
wearable sensors and social network analysis methods.
Mitchell [
          <xref ref-type="bibr" rid="ref43">43</xref>
          ] once defined a social network as “a specific set of linkages among a
defined set of persons, with the additional property that the characteristics of these
linkages as a whole may be used to interpret the social behavior of the persons
involved” (p. 2). Social network analysis [
          <xref ref-type="bibr" rid="ref59">59</xref>
          ] is concerned with both the structure and
the characteristics of relationships between all objects that are part of a certain
system. Moreover, such analyses seek to identify the determinants and consequences of all
present relationships. Since organizations can be viewed as social groupings, Tichy et
al. [
          <xref ref-type="bibr" rid="ref56">56</xref>
          ] propose to use a social network approach in organizational settings, which is
rooted in the fields of anthropology (e. g., [
          <xref ref-type="bibr" rid="ref17 ref38">17, 38</xref>
          ]), role theory (e. g., [
          <xref ref-type="bibr" rid="ref33">33</xref>
          ]), and
sociology (e. g., [
          <xref ref-type="bibr" rid="ref54">54</xref>
          ]). Ever since, organizational social network analysis has been applied
in a variety of ways in at least as many different contexts. For social network analysis,
including those in organizational settings, objective, subjective as well as sociometric
data can be collected. Hitherto, for the most part, network data have been collected by
means of attributional/reputational, decisional, interactional, and positional analyses,
each with their own strengths and weaknesses [
          <xref ref-type="bibr" rid="ref56">56</xref>
          ]. For example, interactional
analysis leads to reliable data, but is a rather costly method in terms of administration and
management. Kilduff &amp; Brass [
          <xref ref-type="bibr" rid="ref35">35</xref>
          ] highlight current leading ideas in organizational
social network research, such as the focus on (dyadic) relationships between actors, and
that such social relations are generally believed to impact various outcomes at the
individual and group level. Using a longitudinal research design, for example, Fowler &amp;
Christakis [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ] demonstrate a link between both direct and indirect ties on happiness.
That is, an individual’s happiness appears to be associated with the happiness of
individuals up to three degrees removed from the actors under investigation. However,
Fowler &amp; Christakis [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ] did not investigate organizational social networks in
particular. A meta-analysis by Pinquart &amp; Sörensen [
          <xref ref-type="bibr" rid="ref49">49</xref>
          ] combines findings from hundreds of
past empirical studies, and arrives at the conclusion that, amongst others, having social
contacts is positively associated with subjective well-being. Especially the quality of
contacts seems to matter. Neither the study by Fowler &amp; Christakis [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ] nor the one
by Pinquart &amp; Sörensen [
          <xref ref-type="bibr" rid="ref49">49</xref>
          ] based the analysis on objective measures of happiness or
well-being.
5.2
        </p>
      </sec>
      <sec id="sec-4-3">
        <title>Data-Driven Framework for Estimating Happiness</title>
        <p>
          Current research on happiness mainly focuses on self-reporting like the day
reconstruction method [
          <xref ref-type="bibr" rid="ref32">32</xref>
          ] and experience sampling [
          <xref ref-type="bibr" rid="ref21">21</xref>
          ]. Although these research methods have
strong advantages, they also have disadvantages which can be compensated by use of
mobile devices, sensor networks and wearable sensors.
        </p>
        <p>Figure 2 depicts a sketch of the data-driven framework for estimating happiness
using social sensing: In that way, objective data can be measured in order to allow
predictions, and ultimately also to influence individuals (for adapting/change their
behavior) in order to increase their well-being and happiness, e. g., using recommendations.
In particular, self reporting is in essence intrusive. It requires effort from participants
which negatively affects participation rate. And by being intrusive self-reporting never
really captures the happiness of participants in the moment of reporting, the reporting
actually takes participants out of the moment, so to say. In the case of the day
reconstruction method we rely on the participants ability to recollect and remember happiness
measurements at the end of a day, which makes these reports susceptible to hindsight
bias and desirability bias. By establishing non-verbal measurements of happiness we
aim to increase participation rates and hope to find a closer proxy for experienced
happiness in the moment.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Conclusions</title>
      <p>In this paper, we focused on perspectives for estimating happiness using social sensing
in the context of complex organizational networks. In particular, we described a
computational social sensing method using wearable sensors for observing physical interaction
networks. For that, we discussed first results, also towards deriving according happiness
indicators given by the respective contact behavior. Finally, we provided an outlook on
how to estimate happiness, and discussed a data-driven framework that incorporates
estimation, prediction, as well as recommendations in order to influence participants for
increasing their experienced level of happiness and well-being.</p>
      <p>
        In the context of this paper, it is important to note that we so far focus on the first
component of happiness (as discussed above), i. e., happiness as the affective
component in event-based or group-based scenarios like student groups, startups, or
conferences etc. For future work, we then aim for different instantiations of the framework
sketched above. Once we have collected the non-verbal data of participants by means
of social interaction data we can then develop predictive models based on this data,
using social network analysis and mining methods, e. g., [
        <xref ref-type="bibr" rid="ref12 ref22 ref26 ref37 ref52 ref6 ref7">6, 7, 12, 22, 26, 37, 52</xref>
        ]. We will
then use the individual predictions to recommend activities to participants via the same
wearable device that captures the social interaction data. Following these
recommendations we expect participants to increase their experienced happiness in the moment.
      </p>
    </sec>
  </body>
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