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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Leveraging Artificial Intelligence to Fight (Cyber)Bullying for Human Well-being: The BullyBuster Project</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Giulia Orrù</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Antonio Galli</string-name>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vincenzo Gattulli</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Michela Gravina</string-name>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stefano Marrone</string-name>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marco Micheletto</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Angela Procaccino</string-name>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Wanda Nocerino</string-name>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Grazia Terrone</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Donatella Curtotti</string-name>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Donato Impedovo</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gian Luca Marcialis</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Carlo Sansone</string-name>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Tor Vergata University</institution>
          ,
          <addr-line>Via Columbia 1, 00133 Roma</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Bari</institution>
          ,
          <addr-line>Via Edorado Orabona 4, 70121, Bari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>University of Cagliari</institution>
          ,
          <addr-line>piazza d'Armi, 09123, Cagliari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>University of Foggia</institution>
          ,
          <addr-line>Via Antonio Gramsci 89, 71122 Foggia</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>University of Naples Federico II</institution>
          ,
          <addr-line>Via Claudio 21, 80125 Naples</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Bullying and cyberbullying are phenomena which, due to their growing difusion, have become a real social emergency. In this context, artificial intelligence can be a powerful weapon to identify episodes of violence and fight bullying both in the virtual and in the real world. Through machine learning, it is possible to detect the language patterns used by bullies and their victims and develop rules to detect cyberbullying content automatically. The BullyBuster project merges the know-how of four interdisciplinary research groups to develop a framework useful for maintaining psycho-physical well-being in educational contexts.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Bullying</kwd>
        <kwd>Detection</kwd>
        <kwd>Crowd</kwd>
        <kwd>Text analysis</kwd>
        <kwd>Keystroke dynamics</kwd>
        <kwd>Deepfake</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>addressing bullying and cyberbullying. The BB approach
integrates cutting-edge AI techniques with psychological
Bullying and cyberbullying are pervasive social issues models to create tools that can efectively assess the risk
that adversely afect the well-being and mental health of of perpetuating, assisting, or sufering from bullying and
millions of children adolescents and adults worldwide. violence in both physical and digital environments. The
These harmful behaviors impact the immediate victims BB research group has gained significant experience
durand contribute to a toxic environment in educational ing the project, and their preliminary results have earned
institutions, workplaces, and online spaces. With the them recognition, including selection for inclusion in the
growing reliance on digital platforms for communica- “Maker Faire European Edition 10th Anniversary Book”
tion and socialization, the need to develop innovative and selection as a promising project by the “Research
solutions to identify, prevent, and address bullying and Centre on Artificial Intelligence under the auspices of
cyberbullying has become increasingly critical. UNESCO” (IRCAI) in the Global Top 100 list of AI projects</p>
      <p>In this paper, we present the “BullyBuster - A frame- addressing the 17 United Nations Strategic Development
work for bullying and cyberbullying action detection Goals1.
by computer vision and artificial intelligence methods
and algorithms” project (BB), funded under the tender
relating to Projects of Relevant National Interest (PRIN) 2. The BullyBuster framework
in 2017, which involves four multidisciplinary research
groups belonging to four universities in Southern Italy
(University of Bari Aldo Moro, University of Cagliari,
University of Foggia, University of Naples Federico II).</p>
      <p>This interdisciplinary project combines artificial
intelligence, technology, law, and psychology expertise to
develop a comprehensive framework for detecting and</p>
      <sec id="sec-1-1">
        <title>In this section, we will go through the core modules of</title>
        <p>the BullyBuster architectural framework, as depicted in
Figure 2. The BullyBuster project’s (Figure 1) purpose is
to integrate behavioural biometrics, content analysis and
crowd analysis into computer vision systems in order to
detect all of the behaviours and indications that might
define a bullying occurrence. The system, in particular,
may be separated into four modules: (1) a module for
crowd analysis for identifying through video-surveillance</p>
      </sec>
      <sec id="sec-1-2">
        <title>1https://ircai.org/top100/entry/bullybuster-a-framework-for</title>
        <p>bullying-and-cyberbullying-action-detection-by-computer-visionand-artificial-intelligence-methods-and-algorithms/
camera potential bullying incidents; (2) a text analysis
module, that analyze textual content for the detection of
signs of bullying or cyberbullying, (3) a third module of
keystroke dynamics analysis to assess a potential victim’s
emotional state; and (4) a module of deepfake detection,
to prevent the spread of malicious multimedia content
on social networks and chatlines. These modules have
been designed based on the psychological modeling of the
behavior of bullies, victims, and spectators. The proposed
solutions have been studied from a legal and juridical
point of view to resolve the crucial aspects of privacy
and data protection.</p>
        <sec id="sec-1-2-1">
          <title>2.1. Behavioural modeling of the phenomenon</title>
          <p>
            Bullying is a repeated, aggressive and anti-social
behaviour of one or more individuals against a specific
victim. It can have severe and long-term consequences
for the victim’s mental, emotional, and physical
wellbeing [
            <xref ref-type="bibr" rid="ref23">1</xref>
            ]. Anxiety, sadness, low self-esteem, social
isolation, and even suicidal thoughts or behaviours may
be experienced by victims [2]. To build safe and
inclusive environments for everyone, it is critical to identify
and prevent bullying in all manifestations. Screening
for (cyber)bullying behavioural indicators, both for
perpetrators and victims, is critical for early detection and
intervention. Schools, parents, and communities can take
appropriate action to support victims and prevent
bullying behaviours by recognizing these signals. In Italy,
various strategies are being employed to combat these
harmful behaviours, including education and awareness
programs, online safety education and anti-bullying
policies that discourage negative behaviour and spread a
mental and cultural attitude emphasising diversity and
tolerance [3].
          </p>
        </sec>
        <sec id="sec-1-2-2">
          <title>2.2. Legal and juridical aspects</title>
        </sec>
      </sec>
      <sec id="sec-1-3">
        <title>In Italy, prevention is carried on by promoting a cultural</title>
        <p>and social environment that discourages such behaviour
and difuses a mental and cultural attitude that
emphasizes diversity and tolerance as a mean of mutual
enrichment thanks to the eforts of the Ministry of Education,
University and Research. The cyberbullying detection is
in charge of Ministry of Justice as it was recently
acknowledged as a crime by the Italian Law no. 71 from June,
18th, 20172. This law oficially described the criminal
action of “cyberbullying” and the way (rules,
investigative tools, burden of proof) to prevent and counter it.
Moreover, it has been promoted the National
Cyberbullying Observatory (http://www.cyberbullismo.com/), by
which it is possible to report these criminal acts. In
particular, the smartphone application named “Youpol” was
implemented thanks to the eforts of Ministry of Internal
Afairs and released for public use. This app allows
reporting several criminal actions, including bullying and
cyberbullying. The legal basis of the research is the art.
9, lett. j) GDPR:
1. [. . . ] processing of genetic data,
biometric data for the purpose of uniquely
identifying a natural person, shall be
prohibited. 2. Paragraph 1 shall not apply if
one of the following applies: [. . . ]
j. processing is necessary for archiving
purposes in the public interest, scientific
or historical research purposes or
statistical purposes in accordance with Article
89(1) based on Union or Member State law
which shall be proportionate to the aim
pursued, respect the essence of the right
to data protection and provide for
suitable and specific measures to safeguard
the fundamental rights and the interests
of the data subject.</p>
      </sec>
      <sec id="sec-1-4">
        <title>2http://www.gazzettauficiale.it/eli/id/2017/06/3/17G00085/sg</title>
        <p>From the privacy point of view, the Garante per la
protezione dei dati personali3 , the italian authority
responsible that people’s privacy is not violated, recently allowed
the installation of video surveillance cameras in the
Istituto Galileo Ferraris in Verona. Furthermore, in Italy, Figure 3: Anomaly detection pipeline. (1) A subset of the
with Law No. 71, May, 29th, 2017, the use of “special in- total frames is selected from the whole sequence of frames;
vestigative tools”, without identifying people, is admitted. (2) Low-level features are extracted to obtain the number of
It represents a considerable motivation to elaborate by groups in each scene; (3) High-level features compute statistics
technicians new forms of electronic evidence to meet as of dynamics patterns; (4) Anomalies are obtained through
soon as possible the legislative needs. thresholding a specific pattern.</p>
        <sec id="sec-1-4-1">
          <title>2.3. Physical violence detection</title>
          <p>Understanding human behaviours and actions through
images and videos can be highly beneficial in the fight
against bullying. Physical violence, isolation, or other
physical patterns such as encirclement are among the
behavioral “indicators” that can signify the presence of
a problem, both as a victim and as a bully. Based on
these psychological models, designing a computer vision
system to identify and report anomalous occurrences
attributed to bullying is possible. With this purpose, we
designed a novel descriptor for crowd behavior analysis
and anomaly detection [4]. It enables the observation of
groups of persons that are not individually identifiable
but can provide enough information to detect violence Figure 4: Demonstrator of the crowd analyzer built into the
or panic. The created technique, inspired by the concept BullyBuster framework. The system detects suspicious
beof the one-dimensional Local Binary Pattern algorithm haviour and reports it to a human operator.
(1D-LBP) [5], aims to evaluate the speed of creation and
disintegration of crowd groups using appropriate
patterns. The number of groups observed in a time interval images, videos, etc.) to cause harm to another person,
can discriminate an ordinary scene from an abnormal referred to as a victim. The following definition is very
one. We hypothesize that abrupt changes in the number close to cyberbullying, which is “an intentional aggressive
of groups are caused by an anomalous occurrence, which act by an individual or group of individuals, using
elecmay be recognized by translating these variations onto tronic forms of contact, repeated over time against a victim
a temporal sequence of strings, which will be consider- who cannot easily defend himself or herself” [6]. Unlike
ably diferent from those corresponding to a condition standard forms of bullying, Cyberbullying is very
danwithout anomalies (3). Through these algorithms, we gerous because it can be perpetrated anywhere, anytime,
have developed a detector that analyzes a video sequence and victims cannot often stop or reduce the spread of
and returns the probability of anomaly in the scene. The these activities [7].
system alerts the human operator when this anomaly This project branch focuses on cyber aggression
(texexceeds a certain threshold, as shown in Figure 4. tual or verbal), starting from textual comments of various
post-Italians on Twitter through innovative steps of
Fea2.4. Verbal abuse detection ture Engineering, including slang and modern and
closeto-aggressive speaking methods. According to the
preCyberbullying is a widespread phenomenon that gener- viously reported definition, Cyberbullying is a repeated
ally includes discrimination, aggression, and harassment. cyber-attack by one or more users against one or more
This phenomenon has become more widespread due to specific victims, repeated in multiple posts over time.
new communication channels allowing people to send An example of victims of these attacks are “celebrities”
and receive messages worldwide. The definition of cyber- who are constantly attacked on their public profiles. In
bullying has, among its consequences, cyber aggression. addition, actual conflicts arise from these aggressive
comCyber aggression is defined as aggressive behavior exer- ments between users with diferent thoughts. The goal
cised on the Internet that uses digital media content (text, was to search for recurring patterns in the wording of
sentences or types of attacks. First, we focused on the
type of language used by the attackers, noting that in
3http://www.garanteprivacy.it/web/guest/home/docweb/-/docwebdisplay/docweb/1651744
• Presence of bullying terms (KW). A Boolean value
indicates cyberbullying keywords (e.g., idiot,
stupid, jerk, clown, whale, trash, ...). In this case,
a vocabulary containing 359 terms identified as
insults and possible insults was created.
• Comment length (L). This feature represents the
length of the comment in terms of words. It has
been noted that most negative comments consist
of only a few words, usually no more than three.</p>
          <p>The innovation related to this branch is Feature
Engineering, dictionary creation, and a Dataset of aggressive
and non-aggressive comments. The models used and
tested are basic Shallow learning approaches to testing
features[13].
2.5. Stress detection
almost all cases, it turns out to be approximate, full of
expressions and words belonging to a vulgar jargon that
leaves little room for misunderstanding; this led to
thinking about the possibility of working with a list of these
words, to recognize them in a comment. Next, it was
noted how to measure a word’s weight in a sentence,
both negative and positive. Again, it was noticed that
some negative comments were written in capitals as if to
simulate a higher tone of voice. This led to thinking of
a way to keep track of this peculiarity. Finally, another
feature highlighted was the presence of the word “no/not”
(“not” in English) in the aggressive comments; in many
cases, it was noted that the aggression sessions began
with this word to contradict the victim. All these
observations were the basis for determining the right features to
extract in the preprocessing phase. This study was
conducted through Twitter comments in Italian, a language
little used in the current state-of-the-art studies.</p>
          <p>The Feature Engineering created is considered because
they have been studied and analyzed. In contrast, others
were considered because they have been exploited in
some state-of-the-art studies, namely: Number Negative
words (BW), Number of “not/not” (NN), Uppercase (U),
Positive/Negative weight of the comment (PW/NW), Use of
the second person (SP), Presence of threats (TR), Presence
of bullying terms (KW), Comment length (L).</p>
          <p>More specifically, based on the feature, it was deemed
appropriate to create a dictionary as well:
In the context of (cyber)bullying detection and
prevention, there is a growing need to identify and prevent
negative emotional states of users while they engage in
online communication. Afective computing, the ability
to recognize users’ emotional states, has been an
ambition in this field for some time. However, current
technologies are either expensive or obtrusive, making them
impractical for widespread use. An alternative solution
is Keystroke Dynamics (KD), which uses behavioural
biometrics to identify or verify a person’s identity by
analyzing habitual rhythm patterns they use while typing
• Number of negative words (BW). Through a “Bad- on a keyboard.</p>
          <p>
            Word” vocabulary containing 540 extremely vul- On this line, we focused on the application of KD to
gar negative words used for aggressive purposes, continuously anticipate users’ emotional states during
insults, and humiliation [8]. message-composing sessions [14]. In particular, in the
• Number of “not/not” (NN). Using “no/not” within study we introduced a time-windowing approach that
ala sentence completely changes the sentence’s lows for the analysis of users’ writing sessions in various
meaning from positive to negative or vice versa. batches, even when the writing window under
consideration is quite brief. This approach is particularly relevant
• Uppercase (U). This is a Boolean value that indi- in the world of social media, where communications are
cates whether the comment is capitalized. It can frequently shared quickly and sparingly. The results
be interpreted as an attack on someone [9]. of the study suggest that even extremely brief writing
• Positive/negative comment weight (PW/NW). This windows (on the order of 30 seconds) are suficient to
recfeature includes two values: the positive and neg- ognize the subject’s emotional state with the same level
ative weight of the comment within the range of accuracy as systems based on the analysis of longer
[
            <xref ref-type="bibr" rid="ref23">0,1</xref>
            ]. For this purpose, each word’s synset and writing sessions. This finding is significant in the context
relative weight were extracted using WordNet of cyberbullying detection and prevention, as it enables
and SentiWordNet [
            <xref ref-type="bibr" rid="ref11 ref12 ref28 ref32">10</xref>
            ]. real-time identification of negative emotional states, such
• Use of the second person (SP). This Boolean value as anger or sadness, during online communication. By
indicates the presence or absence of a second using KD to detect and prevent cyberbullying, it may be
singular or plural form in the comment. This possible to reduce the emotional harm caused by these
feature was extracted through a specially created negative interactions and promote healthier online
comdictionary containing 24 words [11]. munication.
• Presence of threats (TR). incitement to violence, or
suicide. These expressions were identified using a 2.6. Manipulated video content detection
specifically dedicated vocabulary containing 314
violent or inciting words [12].
          </p>
        </sec>
      </sec>
      <sec id="sec-1-5">
        <title>The issue of face-manipulated videos has gotten a lot of attention in the last two years, especially after the</title>
        <p>data and determines the presence of deepfakes,
violent comments, and stress levels. The outcome
is a report that the instructor can consult; it
provides the percentage risk of cyberbullying actions
for the specific modules and the overall risk for
the class.
introduction of deep fake technology, which uses deep
learning technologies to change the identity of people
in images or videos. In the context of cyberbullying, the
seriousness of the problem is indicated by the fact that
even a single person’s act can spread extensively and be
repeated by others, resulting in repetition and an
imbalance of power. The problem is worsened by the ability of
current mobile devices to generate counterfeit content
with a simple application. For these reasons,
developing trustworthy algorithms for appropriately classifying
videos as real or fake, i.e., deepfake detectors, is critical.
Although many deepfake detectors have achieved
excellent accuracy levels, generalization remains a significant
challenge. Deepfake detectors, in particular, can identify
just the manipulations on which they have been trained.
For the BullyBuster deepfake detector, we exploited the
complementarity of diferent individual classifiers with
appropriate fusion rules to increase the generalization
capacity of modern deepfake detection systems [15, 16].
Moreover, we designed a novel deepfake detection
approach based on the Discrete Cosine Transform (DCT)
representation of manipulated and original images at
diferent scaling and compressing levels [17].</p>
        <sec id="sec-1-5-1">
          <title>2.7. Prototype and use cases</title>
        </sec>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>3. Conclusions</title>
      <sec id="sec-2-1">
        <title>The BullyBuster framework takes into account three dif</title>
        <p>ferent use cases:
Bullying and cyberbullying are social issues that afect
individuals and communities on various levels. They have
• The BB questionnaire aims to collect data from broader implications for the overall well-being and safety
specializing the BullyBuster automatic tools. The of the social environment because they afect the
individstudent watches animated videos illustrating bul- ual’s mental health and disrupt social relationships. The
lying and cyberbullying before completing the BullyBuster project presents a comprehensive,
multidisquestionnaire. We chose questions based on psy- ciplinary approach to addressing the pervasive of these
chological analyses to assess how much a per- issues. The framework addresses many aspects of these
son’s actions in real life and on the internet put phenomena in both physical and digital environments by
them at risk of perpetuating, helping, or sufer- combining cutting-edge artificial intelligence algorithms,
ing bullying and violence. The development of computer vision, and psychological models. The
partthe questionnaire and data collection was car- nership of four Southern Italian universities resulted in
ried out in compliance with the aspects of pri- a comprehensive system that includes crowd analysis,
vacy and ethics. text analysis, keyboard dynamics, and deepfake detection
• The “Teacher Tool” enables the teacher to trans- modules. The BullyBuster framework has demonstrated
fer data obtained from the class chat and videos efectiveness in recognizing and preventing bullying and
retrieved from the video surveillance system to cyberbullying events. Its modular design enables
ongoa desktop application and evaluate them using a ing improvement and adaptation to new challenges and
deepfake detector, a text analyzer, and a crowd technical advances. Furthermore, the legal and juridical
analyzer. The system generates a report that in- component of the project assures that the developed
socludes the risk percentages of bullying/cyberbul- lutions comply with privacy and data protection rules,
lying behaviors for each module and the overall making the BullyBuster framework a feasible and
ethirisk percentage for the class. cal solution for educational institutions, workplaces, and
• The “Guided discussion tool” requires students to online platforms.</p>
        <p>utilize the Bullybuster chat software on the
desktop machines in the school’s computer room to
discuss an assigned topic (environment, politics,
current events, etc.). The system analyzes chat</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>4. Acknowledgment References</title>
      <sec id="sec-3-1">
        <title>This work is supported by the Italian Ministry of Ed</title>
        <p>ucation, University and Research (MIUR) within the
PRIN2017 - BullyBuster - A framework for bullying
and cyberbullying action detection by computer vision
and artificial intelligence methods and algorithms (CUP:
F74I19000370001). The project has been included in the
Global Top 100 list of AI projects addressing the 17
UNSDGs (United Nations Strategic Development Goals) by
the International Research Center for Artificial
Intelligence under the auspices of UNESCO.</p>
      </sec>
    </sec>
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