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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Introducing empathy into recommender systems as a tool for promoting social cohesion</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Alan Wecker</string-name>
          <email>ajwecker@gmail.com</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Tsvi Kuflik</string-name>
          <email>tsvikak@is.haifa.ac.il</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Paul Mulholland</string-name>
          <email>paul.mulholland@open.ac.uk</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Belen Diaz-Agudo</string-name>
          <email>belend@ucm.es</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Thomas Anthony Pedersen</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Aalborg University Copenhagen</institution>
          ,
          <addr-line>A.C. Meyers Vaenge 15, Copenhagen</addr-line>
          ,
          <country country="DK">Denmark</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Instituto de Tecnología del Conocimiento, UCM, Facultad de Informática</institution>
          ,
          <addr-line>Ciudad Universitaria, Madrid</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>The Open University</institution>
          ,
          <addr-line>Walton Hall, Milton Keynes MK7 6AA</addr-line>
          ,
          <country country="UK">Great Britain</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>The University of Haifa</institution>
          ,
          <addr-line>199 Aba Khoushy Ave, Mount Carmel, Haifa</addr-line>
          ,
          <country country="IL">Israel</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Contemporary theories of social cohesion emphasize the importance of people accepting and appreciating differences across social groups. The SPICE project aims to promote social cohesion by researching and developing tools and methods to support citizen curation for groups at risk of exclusion. We define citizen curation as a process in which citizens can interpret cultural objects in order to build representations of their own social group. Other groups can then engage with those interpretations in order to appreciate their perspective. In this position paper we discuss how research into empathy can be used to motivate the design of recommender systems that support people in looking beyond their own group and engaging constructively with alternative perspectives.</p>
      </abstract>
      <kwd-group>
        <kwd>1 Social Cohesion</kwd>
        <kwd>Empathy</kwd>
        <kwd>Recommender Systems</kwd>
        <kwd>Citizen Curation</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Based on work by Pahl (1991) and Friedkin
(2004), among others, social cohesion is argued
by Fonseca, Lukosch &amp; Brazier (2018), to be
“[a] construct that is at the heart of what
humanity currently needs” (p. 231). With a specific
focus on societies within cities, they argue that
social cohesion is one of the main characteristics
of a resilient city, as “[..] fostering social
cohesion in cities means creating societies where
people have the opportunity to live together
with all their differences” (Fonseca et al. 2018,
p. 232). Albeit, not specifically described, what
“opportunity” means in this regard, we argue
that at a minimum it must imply an acceptance
of the other inhabitants, and as such an
acceptance of the differences between oneself,
and the “others”, if not necessarily an
affirmation, nor a complete understanding of these
differences. Hence, in this view, social cohesion
can be regarded on a “higher” level, as a
pinnacle goal of society, embracing individuality, all
the while focusing on group unification through
the acceptance of the idiosyncrasies of the
individual, the groups and the society.</p>
      <p>In the SPICE project, we aim to promote
social cohesion by researching and developing
tools and methods to support citizen curation
for groups at risk of exclusion from
participating in shared culture and interacting with other
groups. Groups we are working with in the
SPICE project include older people, asylum
seekers, children with serious illnesses,
children from lower socioeconomic groups, deaf
people, and children from different religious
and secular communities.</p>
      <p>We define Citizen Curation as a process in
which cultural objects are used as a resource by
citizens to develop their own personal
interpretations (Bruni et al. 2020). Those
interpretations are then shared and used within and across
groups to reflect on similarities and differences
in perspective. Within groups, citizens can use
their interpretations to build a representation of
themselves and their shared perspective on
culture. Citizens from other groups can engage
with those interpretations in order to better
understand alternative perspectives, build
empathy and thereby help to build social cohesion.</p>
      <p>
        Citizen curation can be understood as a form
of museum participation
        <xref ref-type="bibr" rid="ref11">(Simon, 2010)</xref>
        in
which museum visitors, both physical and
virtual, are given opportunities to actively in
engage in culture. Social media platforms offer
one way in which museums can promote
participation among visitors. Social media channels,
in particular Twitter, Facebook and YouTube
are commonly used by museums
        <xref ref-type="bibr" rid="ref18">(Zafiropoulos
et al 2015, Badell 2015)</xref>
        . However, analysis of
museum social media accounts suggests they
are largely used for advertising rather than
public interaction (Badell 2015). More
fundamentally, although social media has the potential to
help people take new perspectives and interact
with a broader range of people
        <xref ref-type="bibr" rid="ref1">(Kim et al.
2010)</xref>
        , in practice the effects of social media are
often negative; people follow others they agree
with (homophily)
        <xref ref-type="bibr" rid="ref10">(Saleem et al. 2017)</xref>
        . This
problem is often further exacerbated by social
media recommender systems that draw users to
people similar to themselves, sharing similar
content.
      </p>
      <p>Therefore, although social media platforms
may help sub-groups to interact with each other,
they often fail to help people to take alternative
perspectives. Consequently, existing social
media platforms, as currently used, would not
provide effective support for citizen curation that
requires citizens to not only look within their
own group but also appreciate other viewpoints
and build empathy toward those that hold them.</p>
      <p>
        Empathy encompasses a number of ways in
which people can respond to each other
        <xref ref-type="bibr" rid="ref17">(Zaki
2019)</xref>
        . These include understanding what the
other person feels (i.e. cognitive empathy),
sharing the emotion of the other person (i.e.,
emotional empathy) and wanting to improve
the experiences of the other person (i.e.,
empathic concern). Historically, empathy was
thought of as a genetic trait that operated as an
instinct or reflex action toward other people.
Contemporary research suggests that empathy
is largely environmental, and that it can change
through life and toward different groups of
people (Bazalgette 2017). In some cases, empathy
levels can be changed relatively quickly with
appropriate interventions
        <xref ref-type="bibr" rid="ref17">(Zaki 2019)</xref>
        .
      </p>
      <p>Currently, recommender systems are in
common use that aim at delivering their users
with relevant information. These can be
particularly important in a social media context, in
helping people to manage a high volume of
continually updated content. In our work we aim to
investigate how empathy can be introduced into
the design of recommender systems in order
that their users can be supported in appreciating
alternative perspectives as a step toward
enhancing social cohesion.</p>
    </sec>
    <sec id="sec-2">
      <title>2. The Challenge: How Can Recommender Systems Promote Empathy?</title>
      <p>
        Traditionally, recommender systems aim at
assisting people in making choices without
sufficient personal knowledge
        <xref ref-type="bibr" rid="ref9">(Resnick and
Varian 1997)</xref>
        . Since they first appeared, in the early
1990s, then called collaborative filtering
systems (Goldberg et al. 1992), they penetrated
every aspect of our lives, as a means to help
users to cope with information overload and
especially, collaborate implicitly on the task. The
cultural heritage (CH) domain is just one area
where recommender systems flourish, as
demonstrated by the survey of Ardissono et al.
(2012). At first, recommender systems aimed
at recommending what seemed to be best for the
user according to the mutual taste of similar
users (collaborative filtering) or according to
personal preferences (content-based filtering).
However, over the years, additional aspects
were considered, including various contextual
aspects
        <xref ref-type="bibr" rid="ref15">(Verbert et al. 2012)</xref>
        and more recently
the idea of serendipity
        <xref ref-type="bibr" rid="ref2">(Kotkov et al. 2016)</xref>
        .
When considering empathy as a means for
enhancing social cohesion, the question is how
can recommender system technology can be
extended to consider the subtle goal of
introducing empathy into its process. The first step may
be finding a way of representing and reasoning
about empathy and then including it in the
recommendation process. When considering
empathy, especially towards groups, we may find
related work in the group recommendation
literature where recommendation for a group is
not solved as a mere aggregation of individual
preferences. For example, in the ARISE
architecture (Architecture for recommendations
Including Social Elements), Quijano et al. (2014)
proposed a recommendation method based on
social behavior within a group including group
characteristics, such as size, structure,
personality of its members in conflict situations, and
trust between group members. Humans are
social individuals and, therefore, social behavior
has a great impact on their group
decision-making processes. It is clear that groups have an
influence on individuals when coming to a
decision. This is commonly referred to as emotional
contagion: the effect of individuals’ affective
state on others in the group
        <xref ref-type="bibr" rid="ref3">(Barsade 2002,
Hatfield et al. 1994, Masthoff 2004)</xref>
        . This
contagion is usually proportional to the tie strength
or trust between individuals as closer friends
have a higher influence
        <xref ref-type="bibr" rid="ref16 ref4">(O’Donovan and Smyth
2005, Golbeck 2006, Victor et al. 2008)</xref>
        .
However, the influence of the group also depends on
the individual’s degree of conformity
        <xref ref-type="bibr" rid="ref3">(Masthoff
2004)</xref>
        . It has been demonstrated that humans
adjust their opinions to conform with those of a
group when the majority of the group expresses
a different opinion. The degree of conformity is
counteracted by the individual’s behavior when
facing a conflict situation. Here, personality
influences the acceptance of others’ proposals
(Recio-Garcia et al. 2009)
      </p>
      <p>People generally have higher levels of
empathy for others from their perceived in-group.
De Waal (2011) argues that this is due to the
tribal nature of humans (and other mammals)
which was necessary for survival. People can
characterize their in-group in different ways,
for example on the basis of race, gender, class,
sexuality, religion, politics or some other
characteristic. Fractures between such groups create
a challenge for social cohesion, in which people
can have empathy toward their own group and
a deficit of empathy toward others.
Technological developments in the 21st Century can be
seen as accelerating the problem. Turkle (2016)
makes a link between a rapid decline in
empathy and ubiquitous access to digital
communications. Spinney (2017) argues that social
media can diverge the shared memories and
identities of different social groups. Can new
technology, and in particular recommender
systems, increase as rather than decrease empathy?</p>
      <p>
        A number of interventions can be made to
increase a person’s empathy toward other
groups
        <xref ref-type="bibr" rid="ref17">(Bazalgette 2017, Zaki 2019)</xref>
        . Many of
these could inform the design of recommender
systems. Contact between groups can promote
empathy by building understanding and an
appreciation of their commonalities.
Recommender systems could suggest social contacts
and content from other groups in order to
promote cross-group contact. Perspective taking,
i.e. seeing the World from someone else's
perspective can promote empathy. This is
particularly the case if the alternative point for view is
presented as a story rather than an abstract,
factual account (e.g. a day in the life of a
homelessness person rather than homelessness
statistics). Evidence suggests that empathic
responses can also be strengthened if the content
is presented in a more intimate media such as
audio
        <xref ref-type="bibr" rid="ref12">(Spence et al 2019)</xref>
        . Recommender
systems could prioritize content that is more
personal, narrative-based and uses media such as
audio. People tend to respond more
empathically if it is seen as a social norm. For example,
when reading a story by an out-group member,
a person is more likely to respond empathically
if their peers have done the same.
Recommender systems could promote online
comments that are empathic so that this is seen as a
social norm. People also tend to respond more
empathically to content if explicitly prompted
to think about the author’s point of view.
Recommender systems could wrap suggested
content in prompts that encourage a productive
response. Finally, people are more likely to
respond empathically if they are not rushed and
have the available time. Recommender systems
could use contextual information (e.g. a
person’s current activity status) to suggest content
when the recipient has the time to respond
empathically.
      </p>
      <p>
        In order to promote empathy across groups,
the recommender system also needs a way of
identifying or constructing those groups.
Within the context of citizen curation, where
visitors are supported in interpreting artworks
for themselves, groups could be constructed by:
1) Social grouping i.e., explicit communities
based on personal attributes such as a group of
friends, or groups created based on age, sex,
race, religion; 2) Grouping based on
preferences for artworks according to their attributes
(e.g. artist, subject matter, style, time period);
3) Grouping by based on the content (including
emotional content) of user interpretations
provoked by the same artwork or similar artworks.
Descriptions of artworks and emotions
combined with the use of ontologies to bring
additional meaning, provides a very rich
combination of knowledge with great potential for
creating such communities. This type of grouping
is related to the semantic similarity assessment
between users. Many community detection
methods have been introduced in recent years,
with each such method being classified
according to its algorithm type. A comprehensive
review can be found in
        <xref ref-type="bibr" rid="ref6">(Plantié and Crampes
2013)</xref>
        . An open research challenge is
understanding which type of community detection is
most effective for building of empathy and
social cohesion.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. An Illustrative Scenario</title>
      <p>The following scenario illustrates how
empathy research could motivate the design of a
recommender system.</p>
      <p>Lara decides to take part in a Citizen
Curation activity on the website of her local museum.
The activity involves selecting an artwork from
the museum's collection, adding her own
interpretation and sending this to a friend. She
decides to record her interpretation as audio
rather than text or video. She also chooses to
make her interpretation shareable
anonymously with other museum visitors. Later in the
day when relaxing at home, Lara is notified of
an interpretation of the artwork contributed by
someone from another social group with whom
she rarely interacts. The interpretation is a
personal story prompted by the artwork recorded
as audio. The story is accompanied by
comments responding positively to the story
contributed by people in Lara's social group. Lara
decides to listen to it. Before the audio
recording starts, Lara is encouraged to imagine how
the storyteller feels about what happened. The
story is very different to Lara's interpretation of
the artwork. She adds her own comment after
listening.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Practical Challenges and Possible</title>
    </sec>
    <sec id="sec-5">
      <title>Solutions</title>
      <p>When considering the idea of empathy, a
number of practical challenges arise: How to
reason about it? What reasoning process may
enable to enhance empathy towards
different groups of people? How this process
depends on the personal characteristics of the
individual user? When considering the SPICE
citizen curation scenario in particular, the
following practical challenges arise:</p>
      <p>Contact: How to detect group membership
and use this to put people in contact with other
social groups</p>
      <p>Perspective: How to detect and recommend
diverse content from alternative perspectives.</p>
      <p>Stories: How to detect personal,
narrativebased content and prioritize for
recommendation (given that it may be more empathic)</p>
      <p>Social norms: How to detect and prioritize
positive replies from the reader’s own social
group to content from other groups?</p>
      <p>Wrappers: How to wrap recommendations
in prompts that encourage an empathetic
mindset? How does this relate to personality?</p>
      <p>So, we see that empathic recommendation
requires much more than just recommending
the most appropriate content and goes beyond
simple diversity in recommendation. It
includes the need to reason about social groups,
the nature of the content, social norms, and
develop appropriate wrappers for presenting the
right content in a way that will promote
empathy. Questions concerning ethical
considerations also arise, including: What are considered
legitimate methodologies to use in order to
promote social cohesion via empathy and what
would be considered unwarranted
manipulations?</p>
      <p>In addition, how do we measure social
cohesion, in order to evaluate the success of our
methodology? Can we measure empathy? Can
we measure increases in empathy towards other
groups? Previous research suggests ways in
which empathy can be measured. Baron-Cohen
and Wheelwright (2004) developed the
Empathy Quotient, which is a self-report test of
empathy. Zaki (2019) reports on a number of ways
empathic concern can be measured from
behaviour such as a willingness to help someone in
need or to give to charity. Within the context of
citizen curation, empathy could potentially be
detected from the interpretations and comments
of visitors, for example the extent to which they
demonstrate perspective taking.</p>
      <p>Potential solutions that are considered by the
SPICE project include combining a personal
user model with models of groups s/he may
belong to. The personal user model may include
personal characteristics that may help a system
reason about what interests the person, together
with personality that may guide content
selection and delivery. The group models may help
in selecting content that may present different
groups, similar or different from those the user
belongs to in order to cause awareness and
possibly promote empathy towards them.</p>
    </sec>
    <sec id="sec-6">
      <title>5. Conclusions</title>
      <p>Contemporary theories of social cohesion
emphasize the importance of appreciating
differences across social groups. Social media can
potentially support the sharing of alternative
perspectives across groups. However, currently
such technology often leads people toward
content that fits their own viewpoint, promoting
fragmentation rather than cohesion. Research
into empathy suggests how this problem could
be addressed by supporting people in engaging
positively with the perspectives of other groups.
We are applying this work in the cultural
heritage domain, by developing tools and methods
for citizen curation, in which citizens are
supported in developing and sharing interpretations
within and across social groups.</p>
    </sec>
    <sec id="sec-7">
      <title>6. Acknowledgements</title>
      <p>This project has received funding from the
European Research Council (ERC) under the
European Union's Horizon 2020 research and
innovation programme (grant agreement n°
870811).
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