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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>The role of sarcasm in hate speech. A multilingual perspective</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Simona Frenda</string-name>
          <email>simona.frenda@unito.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Dipartimento di Informatica, Universit`a degli Studi di Torino</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>PRHLT Research Center, Universitat Polit`ecnica de Val`encia</institution>
          ,
          <country country="ES">Spain</country>
        </aff>
      </contrib-group>
      <fpage>13</fpage>
      <lpage>17</lpage>
      <abstract>
        <p>The importance of the detection of aggressiveness in social media is due to real effects of violence provoked by negative behavior online. For this reason, hate speech online is a real problem in modern society and the necessity of control of usergenerated contents has become one of the priorities for governments, social media platforms and Internet companies. Current methodologies are far from solving this problem. Indeed, several aggressive comments are also disguised as sarcastic. In this perspective, this research proposal wants to investigate the role played by creative linguistic devices, especially sarcasm, in hate speech in multilingual context.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The web facilitates the large resonance of
hate speech, inciting racism, misogyny or
xenophobia also in the real world. Actually,
it is common that misbehaviours online are
traduced in physical attacks, such as rapes
or bulling. For instance,
        <xref ref-type="bibr" rid="ref9">Fulper et al. (2014)</xref>
        demonstrated the existence of a correlation
between the number of rapes and the amount
of misogynistic tweets per state in USA,
suggesting the fact that social media can be used
as a social sensor of violence.
      </p>
      <p>In addition, the persistence and
diffusion of misogynistic or offensive content can
hurt and distress psychologically the victims,
causing sometime their suicide, such as the
case of the teenager Amanda Todd in 20121.
In order to contrast the origin of these hate
1https://www.theguardian.
com/commentisfree/2012/oct/26/
events and to monitor the uncontrolled flow
of users texts, several initiatives have been
taken in the last years. An example is the
campaign No Hate Speech Movement 2 of the
Council of Europe for human rights online.</p>
      <p>
        The growing interest of NLP (Natural
Language Processing) research community is
demonstrated by the proposal of national
and intern
        <xref ref-type="bibr" rid="ref1">ational workshops (such as ALW
2018</xref>
        3) or campaigns of evaluation fostering
the research in this issue in various l
        <xref ref-type="bibr" rid="ref1">anguages,
such as EvalIta 2018</xref>
        4, IberEv
        <xref ref-type="bibr" rid="ref1">al 2018</xref>
        5 and
SemEval 20196. These initiatives allow to share
amanda-todd-suicide-social-media-sexualisation
2https://www.coe.int/en/web/
no-hate-campaign
3https://sites.google.com/view/
        <xref ref-type="bibr" rid="ref1">alw2018</xref>
        4http://www.ev
        <xref ref-type="bibr" rid="ref1">alita.it/2018</xref>
        5https://sites.google.com/view/
iberev
        <xref ref-type="bibr" rid="ref1">al-2018</xref>
        6http://alt.qcri.org/semeval2019/index.
information and results exploring the
different topics regarding the hate speech online.
As well as, the organizers of these
competitions provide resources such as annotated
datasets that are very costly to obtain.
      </p>
      <p>The fact that the majority of data are
collected from Twitter or Facebook supports the
analysis of the computer-mediated
communication. As well as, the context of short text
incites the creativity of authors who use
figurative devices to express their opinion. One
of the most used figures of speech to manifest
negative opinions is the sarcasm. In fact, it
is used to disguise and, at the same time, to
reinforce the negative thinking, such as:
i) Un pensiero di ringraziamento ogni
mattina va sempre ai comunisti che ce li
hanno portati fino a casa musulmani
rom e delinquenti grazie7.</p>
      <p>
        The ironic sharpness of the sarcasm seems
to be appropriated to express contempt and
to offend individuals subtly. In order to
study this correlation between sarcasm and
hate speech, we proposed the shared task
IronITA8
        <xref ref-type="bibr" rid="ref1">at Evalita 2018</xref>
        that asks
participants to recognize ironic and sarcastic tweets
in a dataset containing also offensive
messages addressed, especially, immigr
        <xref ref-type="bibr" rid="ref1">ants
(Sanguinetti et al., 2018</xref>
        ).
      </p>
      <p>
        Moreover, we participated in two t
        <xref ref-type="bibr" rid="ref1">asks
proposed at IberEval 2018</xref>
        about hate speech:
aggressiveness detection in Mexican Spanish
tweets (MEX-A3T)9 organized by
        <xref ref-type="bibr" rid="ref1">A´
lvarezCarmona et al. (2018</xref>
        ) and identification
of misogynistic English and Spanish tweets
(AMI)10 organized by Fersini,
        <xref ref-type="bibr" rid="ref1 ref2">Anzovino, and
Rosso (2018</xref>
        ). As a confirmation of our
intuition, the systems proposed for these tasks
show some difficulties to classify the
sarcastic abusive tweets. Indeed, sarcasm,
independently from the differences between
languages, disguises the real intention of the
message which is with difficulty recognized
by machine. In line with these early
experiments, IronITA could be a good step of
analysis.
php?id=tasks
      </p>
      <p>7Each morning, I would like to thank communists
who bring home musulmans, roms and delinquents
thanks. Tweet from IronITA corpus.</p>
      <p>
        8http://di.unito.it/ironita18
9https://mexa3t.wixsite.com/home/
aggressive-detection-track
10https://
        <xref ref-type="bibr" rid="ref1">amiibereval2018</xref>
        .wordpress.com/
      </p>
      <p>The rest of the paper is structured as
follows. Section 2 introduces the literature
that inspired our investigation. Section 3
describes our participation in IberEval tasks
with the used approach and obtained results.
In Section 4 we analyze the presence of
sarcasm in analyzed aggressive and offensive
texts. Finally, in Section 5 and 6 we draw
our research proposal and the future work.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related work</title>
      <p>
        The literature about hate speech detection
includes different issues, such as:
cyberbullying, misogyny, nastiness and
aggressiveness. The most commercial methods,
currently, rely on the use of blacklists. However,
filtering the messages in this way does not
provide a sufficient remedy because it falls
short when the meaning is more subtle or
altered by sarcasm. Actually, some authors,
such as
        <xref ref-type="bibr" rid="ref11">Justo et al. (2014)</xref>
        and
        <xref ref-type="bibr" rid="ref13">Nobata et
al. (2016)</xref>
        , underline the fact that sarcasm
makes the interpretation of the message
difficult, generally requiring world knowledge.
Also Smokey, one of the first systems,
implemented by
        <xref ref-type="bibr" rid="ref16">Spertus (1997)</xref>
        , uses syntactic
and semantic rules with lexicons to recognize
flames.
      </p>
      <p>
        In this context, the research is
oriented at investigating deeply the language
using classical
        <xref ref-type="bibr" rid="ref14">(Samghabadi et al., 2017)</xref>
        and deep learning methods
        <xref ref-type="bibr" rid="ref3">(Del Vigna et
al., 2017)</xref>
        . Differently from
        <xref ref-type="bibr" rid="ref12">Mehdad and
Tetreault (2016)</xref>
        and
        <xref ref-type="bibr" rid="ref10">Gamba¨ck and Sikdar
(2017</xref>
        ), for MEX-A3T t
        <xref ref-type="bibr" rid="ref1">ask in Frenda and
Banerjee (2018</xref>
        ) we applied an experimental
technique that combines linguistic features
and Convolutional Neural Network (CNN).
      </p>
      <p>
        For the first time,
        <xref ref-type="bibr" rid="ref1 ref2">Anzovino, Fersini, and
Rosso (2018</xref>
        ) propose a classical machine
learning approach to identify misogyny in
English, comparing different classifiers.
Taking into account this previous work and the
psychological studies about sexism
        <xref ref-type="bibr" rid="ref5">(Ford and
Boxer, 2011)</xref>
        , in Frend
        <xref ref-type="bibr" rid="ref1">a and Ghanem (2018</xref>
        )
we combined sentiment and stylistic
information with specific lexicons involving several
aspects of misogyny online.
      </p>
      <p>In the following section we report how we
addressed the identification of aggressiveness
and misogyny in Twitter, the experiments
carried out and the results obtained.</p>
    </sec>
    <sec id="sec-3">
      <title>Hate speech, aggressiveness and misogyny</title>
      <p>
        Considering our motivations, our early
experiments focus mainly on hate speech
detection. For this purpose, we particip
        <xref ref-type="bibr" rid="ref1">ated
at two tasks at IberEval 2018</xref>
        respectively
about aggressiveness and misogyny
detection.
3.1
      </p>
      <p>Aggressiveness detection
The first task aims to classify aggressive and
non-aggressive tweets in Mexican Spanish.
We applied a deep learning approach
incorporating into CNN architecture a set of
linguistic features (DL+FE) concerning: proper
characteristics of a tweet, such as emoticons,
abbreviations and slang words; stylistic
information, such as the length of tweets, the use
of the punctuation and the uppercase
characters; bags of words weighted with tf-idf;
emotive traits of the aggressiveness; and
derogatory adjectives and vulgar expressions typical
of Mexican culture.</p>
      <p>By means of Information Gain, we
noticed that anger and disgust are the
principal emotions that incite the aggressive
behaviour. We compared this system with a
simple CNN architecture (DL) in order to
understand the contribution of features to deep
learning approach. The measure used for the
competition is F-score for positive class (i.e.
aggressive class). Despite the novel approach,
the results obtained are low and the features
seem not to help deep learning, as showed in
Table 1.</p>
      <p>DL
DL+FE</p>
      <sec id="sec-3-1">
        <title>Prec.</title>
        <p>0.34
0.27
Rec.
0.34
0.38
F-pos
0.34
0.31</p>
      </sec>
      <sec id="sec-3-2">
        <title>Rank</title>
        <p>9
10</p>
        <p>Therefore, in order to understand what
are the difficulties of DL+FE, we carried
out the error analysis. We mainly noticed
that there are several humorous cases,
especially sarcastic (see Section 4), which
are misclassified.
3.2</p>
        <p>Automatic misogyny
identification
ish tweets. In the case a tweet is classified
as misogynistic (Task A), we need to
distinguish (Task B) if the target is an individual
or not (Tar.) and identify the type of
misogyny, according to the following classes (Cat.):
stereotype and objectification, dominance,
derailing, sexual harassment and threats of
violence, and discredit. This subdivision of
misogyny allows us to explore the different
aspects of misogyny and compare them in
two different languages. Moreover, the data
are not geolocalized. Therefore, in order to
gather the linguistic variations and consider
the various traits of misogyny, we proposed
an approach based on stylistic features
captured by means of the character n-grams,
sentiment and affective information, and on a set
of lexicons concerning: sexuality, profanity,
femininity, human body and stereotypes. In
addition, we considered slangs, abbreviations
and hashtags.</p>
        <p>By means of Information Gain, we
discovered some differences between the two
languages: sexual language is more used in
English misogynistic tweets, whereas profanities
or vulgarities are more used in Spanish ones.
For this task, we applied Support Vector
Machine (SVM) and majority voting technique.
To evaluate the Task A the organizers used
Accuracy measure and for Task B the average
Macro-F1 measure. In Table 2 and Table 3
we report the promising results obtained with
better runs for both languages.</p>
        <p>En
Sp</p>
      </sec>
      <sec id="sec-3-3">
        <title>Approach</title>
        <p>Ensemble
Ensemble</p>
        <p>Acc
0.87
0.81
greur et emportement 11, that is a kind of
aggressive and sharp irony addressed a target to
hurt or criticize him without to exclude the
possibility to amuse. This statement is
corroborate by our analyses on English, Spanish,
Mexican and Italian hate speech corpora. As
said above, we carried out the error analysis
for both tasks.</p>
        <p>In the first competition we noticed that
our approach fails in the classification of
sarcastic aggressive utterances, such as:
ii) @USUARIO #LOS40MeetAndGreet 9 .</p>
      </sec>
      <sec id="sec-3-4">
        <title>Por q es una mama´ luchona que cuida a</title>
        <p>su bendicio`n12.</p>
        <p>Actually, the sarcasm is a type of figurative
devices that modifies the perception of
message, hindering the correct detection of hate
speech by automatic systems. We found, in
fact, the same difficulty for the recognition of
misogynistic tweets in both languages, such
as:
iii) ¿Cu´al es la peor desgracia para una
mujer? Parir un var´on, porque despu´es de
tener un cerebro dentro durante 9 meses,
van y se lo sacan13;
iv) What’s the difference between a blonde
and a washing machine? A washing
machine won’t follow you around all day
after you drop a load in it.</p>
        <p>
          In virtual as in real life, sexist jokes are
very common. In general, they are considered
innocent by the majority of people.
However,
          <xref ref-type="bibr" rid="ref5">Ford and Boxer (2011)</xref>
          reveal that
sexist jokes are experienced by women as
sexual harassment as well as offences. Moreover,
          <xref ref-type="bibr" rid="ref6">Ford, Wentzel, and Lorion (2001</xref>
          ) investigate
on the effects of exposure to sexist jokes and
they underline that a continue exposition can
also modify the perception of sexism as norm
and not as misbehavior.
5
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Research Proposal</title>
      <p>These early observations suggest the
necessity to address the use of figures of speech
such as sarcasm, in order to accurate, in
11“type of irony done with sharpness and a fit of
anger”</p>
      <p>12@User #LOS40MeetAndGreet 9 . Because she is
a fighter mother who takes care of her kid.</p>
      <p>13What’s the worst disgrace for a woman? Giving
birth to boy, because after she has got a brain into her
for 9 months, it is taken out
a multilingual perspective, the automated
methods to flag abusive language.</p>
      <p>For this purpose, we propose an accurate
analysis of different kinds of hate speech
online especially in Italian, English and
Spanish, taking into account also the geographical
linguistic variations. We focus in particular
on short texts such as tweets, posts or
comments, exploring the informal language.</p>
      <p>Considering the previous observations, we
propose approaching the hate speech
detection issues taking into account the figurative
dimension of language and especially of
abusive language. Moreover, it is necessary to
examine the appropriateness of various
computational techniques to solve this problem.
In this line, we want to examine the
contribution of the linguistic features to deep learning
approaches by comparison with the
performances of classical techniques. Finally, the
multilingual context allows to discover the
typical aspects of hate speech in order to
recognize it independently from the languages.</p>
      <p>Indeed, the scope of this investigation is to
propose a methodology for monitoring
correctly the user-generated contents allowing
the system to work as sensor of the violence,
also in real world.
6</p>
    </sec>
    <sec id="sec-5">
      <title>Future work</title>
      <p>
        Our research aims to explore the several
dimensions of hate speech considering, above
all, the use of figurative devices that hinder
the automatic processes of recognition. In
order to investigate the remarks observed in
these first experiments, as future work, we
would like to participate in HaSpeeDe14 and
AMI15
        <xref ref-type="bibr" rid="ref1">at Evalita 2018</xref>
        for Italian.
      </p>
      <p>
        In addition, similar tasks are proposed at
SemEval 2019 concerning: multilingual hate
speech against immigrants and women
(HatEval)16, and the identification and
categorization of offensive language in social
media (OffensEval)17. Analyzing different kinds
of abusive language allows to understand the
boundaries between them and their singular
aspects. Finally, multilingual context gives
us the opportunity to delineate the
differ14http://www.di.unito.it/~tutreeb/
haspeede-evalita18/index.html\#
15https://
        <xref ref-type="bibr" rid="ref1">amievalita2018</xref>
        .wordpress.com/
16https://competitions.codalab.org/
competitions/19935
      </p>
      <p>17https://competitions.codalab.org/
competitions/20011
ences and analogies between the various
languages, inferring general characteristics of
hate speech online.</p>
    </sec>
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