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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Can you feel it will you tell me. Encouraging sentiment expression on the web</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Francesco D'Aleo (francescodaleo@gmail.com) DMI</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Universita` degli Studi di Palermo</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Italy</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>via Archirafi -</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Palermo</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Valerio Perticone (valerio.perticone@unipa.it)</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>DMI, Universita` degli Studi di Palermo</institution>
          ,
          <addr-line>Italy 34, via Archirafi - 90123 Palermo</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Giovanni Rizzo</institution>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Marco Elio Tabacchi</institution>
        </aff>
      </contrib-group>
      <fpage>346</fpage>
      <lpage>351</lpage>
      <abstract>
        <p>In a recent trend in web communication, news outlets and blog platforms allow readers to express opinions about what they have read by choosing an associated feeling, or sentiment expression. This emerging trend, fitting between liking and full text comments, has not still found the popularity it should. The thesis of this paper is that this is also due to the way the sentiment choice is presented to the user. In order to test this hypothesis we have devised a pilot experiment; results confirm that a simpler way of choice increases sentiment expression and yields result that are more aligned with ground truth.</p>
      </abstract>
      <kwd-group>
        <kwd>sentiment expression</kwd>
        <kwd>emoji</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        A recent trend in web communication, aimed at improving
engagement of newspapers and blogs readers and favouring
the expression and exchange of feelings between them, is
emerging: a number of news outlets and blog platforms now
allow readers to express opinions about what they have just
read by indicating what kind of feeling – and in some
instances how intensely – they felt during perusal of the article
or news piece (examples of this can be seen e.g. at the
bottom of every article published by Corriere Della Sera
website, the most read Italian newspaper). Expressing sentiments
about a web text sits in the middle between liking
        <xref ref-type="bibr" rid="ref7">(Hampton,
Goulet, Rainie, &amp; Purcell, 2011)</xref>
        and full textual comments
        <xref ref-type="bibr" rid="ref15 ref20">(Perticone, D’Aleo, Rizzo, &amp; Tabacchi, 2015)</xref>
        .
      </p>
      <p>
        In liking users can express their support for content posted
by other users – be it an image, post, short text, video or
any other multimedia artefact – by pressing a specific
button, usually placed under the aforementioned content. The
naming is due to Facebook using the term like to label the
button, but under different nomenclatures (e.g. +1 for Google
Plus) the same function exists in almost any currently used
SN. Liking enjoys an immense popularity, and can certainly
be pinpointed as a fundamental feature of a truly social
internet context
        <xref ref-type="bibr" rid="ref7">(Hampton et al., 2011)</xref>
        , but has a notable limit: the
lacks of correspondence between the syntactic level (liking in
its specific, linguistic meaning) and a semantic level (the
expression of a specific feeling, that can be positive or negative,
idealistic or utilitarian). Liking expresses just a general sense
of support toward the content or the person writing it. This
situation has been exacerbated by SN’s association of
intrinsically positive terms with the act of liking, up to the
paradoxical situation of expressing linguistic pleasure for other
people’s misfortunes in order to support them. Facebook tried to
alleviate this shortcoming of the liking system by
introducing stickers (or cartoonish pictograms), but such system does
not allow unambiguous expression of feelings, as there is no
pre-shared agreement about the meaning of each sticker, and
furthermore selection of a sticker is cumbersome and loaded
from a cognitive standpoint. Full comments allow a gamut
of expressions, limited only by the time at disposal and the
linguistic proficiency of the writer. But it is not usually a
cursory affair: written comments require a high cognitive load
and skills, while liking is just the pressing of a button, as an
atomic operation as it can be on the web.
      </p>
      <p>As such, sentiment expression on the web fits a nice niche
exactly where it is needed: simple enough to be really
appreciated by users’ ephemeral attention, but better adept at
describing and categorizing feelings toward multimedia
material than the simple liking. Despite this, the emerging trend
has not still found the popularity it should.</p>
      <p>The thesis of this paper is that sentiment expression is not
yet widely adopted in lieu of liking (also) because the typical
GUI means employed to deploy it are not simple enough on
the user; to test this hypothesis we have devised a simple
pilot experiment, based on the idea of simplifying user choice
to just one emotion at a click distance (the others being still
available at a two-clicks distance) with the help of automatic
classification techniques.</p>
    </sec>
    <sec id="sec-2">
      <title>Elements</title>
      <p>In this section we give a concise, general description of the
basic elements used to build our experiment. The following
section will describe in more detail the implementation
techniques of such elements as used in the experiment.</p>
      <sec id="sec-2-1">
        <title>Sentiment analysis</title>
        <p>
          Sentiment analysis is a set of techniques through which it is
possible to find, in an automatic fashion, the general
sentiment (or the opinion) expressed within a text.
          <xref ref-type="bibr" rid="ref11">(McKee, 2003)</xref>
          In particular sentiment analysis methodologies allow to find
the polarity of the text to which they are applied. Given an
input text, sentiment analysis methodologies provide as output
its polarity, which could be thought of as a class label. In fact,
sentiment analysis is a specific instance of the more general
class of classification problems, usually solvable through
machine learning algorithms
          <xref ref-type="bibr" rid="ref1">(Buche, Chandak, &amp; Zadgaonkar,
2013)</xref>
          .
        </p>
        <p>Sentiment analysis is employable in various application
fields. In marketing, for example when a new product is
launched in commerce; the producers, analyzing the opinion
of the users, can understand its popularity, if it is appreciated
by the users or not, and why. Moreover, sentiment analysis
can be important during elections; is possible to find if voters
prefer one candidate over another through the opinions that
they express, and so on.</p>
        <p>
          The term opinion mining and sentiment analysis are often
used interchangeably, and with the same meaning intended;
but, as explained in
          <xref ref-type="bibr" rid="ref10">(Liu, 2010)</xref>
          , “the concepts of emotions
and opinions are not equivalent although they have a large
intersection”. It is clear that the emotional state of a
person affect his opinion, but the two things does not overlap
completely. It can be said that opinion mining methodologies
are used to recognize the opinion polarity expressed in a text,
while sentiment analysis methodologies try to guess the
emotional state of the writer. However in this work we focus our
investigation on the sentiment orientation of the readers.
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>Emoji</title>
        <p>Emojis are iconic representations enjoying a vast popularity
on the web, especially since the rise of mobile platforms and
instant messaging tools.</p>
        <p>
          Emoji became available in 1999 on Japanese mobile
phones, and, according to the Unicode Consortium,
“represent things such as faces, weather, vehicles and buildings,
food and drink, animals and plants, or icons that represent
emotions, feelings, or activities”. In 2007 Google completed
the conversion of “enhanced emoticons” to Unicode
privateuse codes, and in 2009 a set of 722 Unicode characters was
defined as the union of Japanese emoji characters. More
pictographs were added in 2010, 2012 and 2014.
          <xref ref-type="bibr" rid="ref4">(Davis &amp;
Edberg, 2014)</xref>
          In November 2013, a survey revealed that 74
percent of people in the U.S. and 82 percent in China stated
that they have used pictographs or cartoonish images in
nonverbal communications with their relatives or friends while
on SN.
          <xref ref-type="bibr" rid="ref18">(Sternbergh, 2014)</xref>
          This suggests that emoji can be
usefully employed to express feelings or emotions in absence
of elements such facial expressions or voice cues. (Wallbott
&amp; Scherer, 1986) The appearance of emoji can vary
significantly in shape, and emoji do not have to look the same on all
devices: for a given emoji, any pictorial representation based
on both the name or the representative glyph is considered an
acceptable rendition. In Table 1 an example of emoji
representing basic feelings is given.
        </p>
        <p>
          As an example of the deployment of pictographs in
sentiment expression, in January 2013, the popular social
network Facebook allowed users to post what they were
feeling, watching, reading, drinking, eating, and more. Using a
drop-down menu, Facebook allowed users to express related
feelings through a sentiment list containing many elements,
such as happy, excited, loved, sad, crazy, blessed, perplexed,
amused, hopeful, and so on.
          <xref ref-type="bibr" rid="ref3">(Constine, 2013)</xref>
          This
functionality has been limited to update status and is not applicable for
comments or shared links. Furthermore, some Italian online
newspapers (such ”Corriere della Sera” and ”Il Secolo XIX”)
and opinion blogs use software that measure audience
sentiment. Commercial products such Vicomi allow readers to
comment multimedia content with one type of reaction such
“funny”, “worried” or “angry”.
          <xref ref-type="bibr" rid="ref9">(Ken-Dror, 2014)</xref>
          This
manual selection is heterogeneous for classes and their associated
icons.
        </p>
        <p>
          As already discussed in the introduction, what is gained in
depth and information retrieval is lost in terms of simplicity,
and the latter systems have not gained the universal
acceptance that liking has. Choosing among different pictograms
is no more a strictly atomic process, and requires direct
action and a modicum of thinking, which makes it transforming
into an habit a more difficult endeavour. While liking has
become a sort of automatic reflex, sentiment expression still has
to really catch on due to users’ general laziness and lack of
concentration or interest
          <xref ref-type="bibr" rid="ref2">(Chen &amp; Lee, 2013)</xref>
          .
        </p>
      </sec>
      <sec id="sec-2-3">
        <title>Expressing feelings through text</title>
        <p>
          Emotions play a central role in everyday interactions.
          <xref ref-type="bibr" rid="ref14">(Perakyla &amp; Sorjonen, 2012)</xref>
          Among researchers there is
still not a set of agreed basic emotions.
          <xref ref-type="bibr" rid="ref12">(Ortony &amp; Turner,
1990)</xref>
          However Ekman and Friesen list six basic emotions
(happiness, anger, disgust, fear, sadness, surprise)
          <xref ref-type="bibr" rid="ref6">(Ekman &amp;
Friesen, 1971)</xref>
          . They are not the only one to list basic
emotions, but also
          <xref ref-type="bibr" rid="ref13">(Parrott, 2001)</xref>
          list another six primary
emotions (love, joy, surprise, anger, sadness, fear), which partly
overlap Ekman’s classification. Parrott also asserts that such
primary emotions are not mutually exclusive when associated
to an opinion, but they may have a different strength
relative to the same opinion. In 1990 Ekman expanded the list
of basic emotions from six to seventeen, including the likes
of contentment, embarrassment, guilt, relief, satisfaction and
shame
          <xref ref-type="bibr" rid="ref5">(Ekman, 1999)</xref>
          . While this expanded classification is
more detailed and nuanced, the original six basic emotion are
still favoured in many instances, and among them automatic
classification and web sentiment expression.
        </p>
        <p>
          In
          <xref ref-type="bibr" rid="ref19">(Strapparava &amp; Mihalcea, 2007)</xref>
          the authors focuses on
the classification of news headlines in terms of emotions and
polarity. The dataset analysed in the paper uses headlines
extracted from information web sites and labelled with a
predefined six emotion labels (anger, disgust, fear, joy, sadness,
surprise) and with a valence indication (positive/negative).
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Method</title>
      <sec id="sec-3-1">
        <title>Participants</title>
        <p>The experimental subjects panel was constituted by 48 degree
students from CS faculty, enrolled by presence. Data were
collected during March 2015. Participants were recruited on
a voluntary basis and they were treated in accordance with
the “Ethical Principles of Psychologists and Code of
Conduct” (American Psychological Association, 1992). Gender
distribution and mean age are shown in Table 3.</p>
      </sec>
      <sec id="sec-3-2">
        <title>Materials</title>
        <p>
          In order to have a base to which compare the results of our
test, we employed the Italian Sentiment Emotion Expression
database (I-SEEdb)
          <xref ref-type="bibr" rid="ref20">(Tabacchi, 2015)</xref>
          . The database is
comprised by 1200 short snippets of text taken from newspaper.
Each snippet is between 200 and 400 characters long, and
belongs to one out of six different categories: Tech, Politics,
Economy, Culture, News and Health; 200 snippets belong to
each category. The snippet have been classified by human
subjects from university background using internet
questionnaires. Subjects were required to perform sentiment
expression on it by selecting among Ekman’s six basic emotions
the one that mostly approximated their feelings, and to grade
such emotion on a five level Likert-like scale from ”un poco”
(a little) to ”molto” (a lot). Each snippet was rated at least
ten times, and in order to grade each snippet, a final score is
computed using the following:
0 å is 1
s0 = argmaxs:s2S @ is2Is
        </p>
        <p>jIsj A
å is
i0 = is2Is0</p>
        <p>jIs0j
where Sfanger, disgust, fear, happiness, sadness, surpriseg
is the set of emotions and is 2 Is are the intensities gathered
(1)
(2)
for the sentiments. s0 and i0 are the emotion extracted and his
associated intensity.</p>
        <p>In order to perform our experiment we selected the twelve
most polarized (i.e. highest scored) snippets, two from each
category. A sample snippet is shown in Table 2.</p>
        <p>It was a complex restoration operation the one done on
”La Fornarina” by Raphael Sanzio. A number of scientific
and imagining experiments have been carried out, using
technical methodologies such as x-rays, false-colour
and reflectography snapshots.</p>
        <p>Category: Tech</p>
        <p>Score: fhappinessg, 4.0</p>
      </sec>
      <sec id="sec-3-3">
        <title>Procedure</title>
        <p>The experiment is fully computer assisted. All the software
is developed in house. Experimental subjects are introduced
into a secluded room where the experiment takes place. They
are seated in front of a computer screen and, after statistic
data gathering (age, gender) the mechanics of the experiment
is explained to them, aided by written instructions whose
screenshot is shown in Figure 1.</p>
        <p>Each subject is randomly assigned to one of the two
possible experimental conditions, with the software taking care of
the right balance between genders and age:</p>
        <p>H0: after each snippet, six emojis representing the six basic
Ekman’s emotions are shown, in random order, plus one
button labelled ”Prosegui” (Next question). The subject
can press on one of the emojis or on the button.</p>
        <p>H1: after each snippet, one emoji representing the emotion
associated with the high I-SEEdb score is shown, plus a
small pop-up button and the ”Prosegui” button. The
subject can click on the emoji, on the pop-up (in which case a
list comprising the other five emotions, again espressed as
emoji, plus a sixth emoj representing indifference will be
shown) or on the button.</p>
        <p>Screenshots from the two conditions are given in Figure
24. In Figure 4 the extended dropdown menu (invoked when
the subject presses the triangle pop-up) is shown.</p>
        <p>As soon as the subject chooses an emotion (or skips the
choice by pressing the ”Prosegui” button, an option he is
explicitly given in the instructions), another snippet is presented
on screen. Each user is presented with the twelve different
snippets.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Results and Discussion</title>
      <p>Results from the experiment are shown in Table 3</p>
      <p>
        Looking at the results of the two text we can see a
considerable difference, in condition H0 the user tend to mix
similar emotion, occasionally because of misunderstandings
about the correspondence of a specific emoji to the associated
emotion (as verified by post-experiment interviews), but more
often because sentiment could not be mutual exclusive and
could ”overlap” each other.
        <xref ref-type="bibr" rid="ref13">(Parrott, 2001)</xref>
        . This may be not
the only reason for such result: Plutchik argues in
        <xref ref-type="bibr" rid="ref16">(Plutchik,
1980)</xref>
        that we can consider emotions like the colour wheel
with in particular eight primary emotions (that includes joy,
anger, disgust, sadness, fear and surprise) who can be
combined to obtain other feeling, for example the combination
of anger and disgust will produce contempt. Izard
        <xref ref-type="bibr" rid="ref8">(Izard &amp;
Izard, 1977)</xref>
        also suggest that new emotions are formed from
a mixture of basic emotions. For these reasons we can
exclude that people that feels sentiment that are combinations
of emotions, fails to associate with a single emoji when they
are allowed a multiple choice.
      </p>
      <p>In the condition H1 the vast majority of subjects choose
the suggested emoji despite having the possibility to select
another one using the drop-down menu (at a one-click
distance). In our opinion this is because, unlike in condition H0,
showing only one isolated emoji helps the subject to more
accurately recognize the feeling aroused by the reading of the
article, and such emotion in most of the cases corresponds to
that expressed by the suggested emoji.</p>
      <p>Moreover, if we consider the number of neutral
classifications of the snippets, H0 presents more neutral classifications
WRT H1. This fact may be a consequence of what was
already said before about emoji’s misunderstanding plus the
non-mutual exclusivity of sentiments. As a partial
confirmation, subjects that are not able to clearly make a choice
prefer to remain neutral, and choose the neutral emoji. This
phenomenon is less pronounced in condition H1, where the
showing of just one emoji may be of help in order to
recognize the appropriate feeling and express it.</p>
      <p>In synthesis, results shown that presenting only one
preclassified emoji instead of the whole gamut (which is always
an option, albeit it requires a bit more effort to be exercised)
produces results that are more in line with ground truth, and,
what is more important for the correct deployment of such a
system in the real world, increases significantly the number
of times users effectively express the emotion, leading to a
better engagement of the user and to more data gathering for
the system to work on.</p>
      <p>As presented in this pilot experiment, the system is not
directly implementable in a real world application:
preclassification of the articles is obviously impossible in social
networks or news outlets where big data are produced and
published. In a real application this problem could be solved
in at least two different ways. One approach would be to use
automatic classification algorithms to derive a ground truth to
use in lieu of the human pre-classification. Even sub-optimal
solutions, as the ones readily available today, would give a
good headstart to initialise the algorithms, and the missing
information could be gathered by the sentiment expression
choices of the first users. Another solution would be to adopt
an hybrid system, where the first classifications would be
done using a condition similar to H0, and as soon as sufficient
data is gathered to form some sort of ground truth the system
would switch its interface to a single-emoji-plus-dropdown
mode. In the context of SN we also need to consider the
previous interactions between users, as strong feelings may
slightly alter the meaning of the expressed emotion.
Furthermore the readers that habitually does not contemplate liking
can be encouraged by the system to express themselves, and
as such an eventual risk of uniformity given by the use of a
restricted set of feelings would be balanced by the increase
in feeling expression. Further improvement of this
methodology could be obtained by employing fuzzy techniques that
treat degrees of emotion as Fuzzy Sets. (Tabacchi &amp; Termini,
2014; Termini &amp; Tabacchi, 2014; Seising &amp; Tabacchi, 2013;
Tabacchi &amp; Termini, 2013, 2012)</p>
      <p>Further research work will be devoted to increase the
cardinality of the experiment and to a better integration of
automatic and manual pre-classification of texts, in order to
further improve the quality of ground truth and to build toward a
real-world implementation of the system.</p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>This work has been partially supported by P.O. F.E.S.R Sicilia
2007-2013 Progetto POSING - Investiamo nel vostro futuro
– l’Europa cresce in Sicilia.
rial. In D. Ciucci, J. Montero, &amp; G. Pasi (Eds.),
Proceedings of the 8th conference of the european society
for fuzzy logic and technology. Atlantis Press. doi:
doi:10.2991/eusflat.2013.30
Tabacchi, M. E., &amp; Termini, S. (2014). Some reflections on
fuzzy set theory as an experimental science. In A. Laurent,
O. Strauss, B. Bouchon-Meunier, &amp; R. R. Yager (Eds.),
Information processing and management of uncertainty in
knowledge-based systems (Vol. 442, p. 546-555). Springer
International Publishing.</p>
      <p>Termini, S., &amp; Tabacchi, M. E. (2014). Fuzzy set theory as
a methodological bridge between hard science and
humanities. International Journal of Intelligent Systems, 29(1),
104-117. doi: 10.1002/int.21632
Wallbott, H. G., &amp; Scherer, K. R. (1986). Cues and channels
in emotion recognition. Journal of personality and social
psychology, 51(4), 690.</p>
    </sec>
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