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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Analysis of open data of a social network in order to identify deviant communities</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Rostislav Mikherskii</string-name>
          <email>mrm03@mail.ru</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dmitry Kuznetsov</string-name>
          <email>dimabrayankuznetsov@mail.ru</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Physico-technical Institute, V.I. Vernadsky Crimean Federal University</institution>
          ,
          <addr-line>Simferopol</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2020</year>
      </pub-date>
      <fpage>98</fpage>
      <lpage>101</lpage>
      <abstract>
        <p>-The system of analysis of open data of the social network Vkontakte is developed and programmatically implemented. Two ways of identification of deviant communities are proposed. The first way is by the number of community subscribers blocked by the social network for violating the rules. The second way, by the presence of common subscribers between the studied community, and the community about which it is precisely known that it is deviant. It is experimentally established that the second method of identification of deviant communities gives the best result.</p>
      </abstract>
      <kwd-group>
        <kwd>big data</kwd>
        <kwd>open data</kwd>
        <kwd>social network</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>
        Analysis of open data from social networks is a
significant area in the field of big data processing. In
particular, an important task for both law enforcement
agencies and social network administrators is to identify
communities of these networks that disseminate socially
dangerous content.Many works that were written recently
have been devoted to discussion of this problem.The work
[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] is devoted to the development of a method for assessing
the degree of connectedness of user profiles of social
networks based on open data. The degree of connectedness
of user profiles is understood as the probability of meeting
profile owners in real life.In [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], a review of methods that
detect the demographic attributes of a user from their profile
and messages is made. In [
        <xref ref-type="bibr" rid="ref3 ref4">3,4</xref>
        ], forms of deviant behavior of
users of the Russian-language segment of the Internet are
examined in detail.In particular, in [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] it was shown that the
main reason for deviant behavior in social networks is
virtuality and anonymity. In [5], according to foreign
sources, a review of the main methods of analysis of social
networks in relation to the task of identifying suspicious and
criminal communities is carried out.
      </p>
      <p>
        To study social networks in terms of social relationships,
the Social Network Analysis (SNA) method is often used.
The SNA method is described in detail in [
        <xref ref-type="bibr" rid="ref6 ref7 ref8">6–8</xref>
        ]. In this
method, the objects of research are the nodes, and the
relationships characterizing the relationship between them.
Nodes can be communities, users of social networks, etc.
The connections between these nodes can be money
transfers, communication, friendship, etc. This method has
been successfully used to study the organization structure of
the Al-Qaida terrorist network [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], to study the network of
terrorist organizations operating in India [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], to analyze the
topological structure of criminal networks, in particular the
network of methamphetamine traffic [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. These research
studies are mainly motivated by the need to find effective
methods to undermine criminal or terrorist organizations.
      </p>
      <p>
        Anorexia-oriented online communities have been studied
in [
        <xref ref-type="bibr" rid="ref12 ref13 ref14">12–14</xref>
        ]. A wide range of issues was studied in these
works, including the construction and management of
member identities, the processes of social recognition, the
emergence of group norms, and the use of linguistic markers.
Similar studies have been conducted for groups promoting
suicidal behavior [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
      </p>
      <p>
        In [
        <xref ref-type="bibr" rid="ref16 ref17 ref18 ref19 ref20">16-20</xref>
        ], the categorization of pornographic content
and the frequency of its use were studied.
      </p>
      <p>
        In [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ], the authors also focused on consumption
networks for adult content, which is present in many online
social networks and on the Internet as a whole. The authors
of this work investigated how such communities interact
with the entire social network. They found that few small and
closely related communities are responsible for much of the
production of content. Produced content is distributed
through the rest of the network mainly directly or through
bridge communities, reaching at least 450 times more users.
In this work, a demographic analysis of the networks of
producers and consumers of adult content was also carried
out. It has been shown that it is possible to easily identify
several key users in order to radically eradicate the process
of distribution of pornographic content.
      </p>
      <p>
        The issue of community polarization in social networks
was studied in detail in [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ]. It proposed a new polarization
metric based on the analysis of the boundary of a pair of
(potentially polarized) communities, which better reflects the
concepts of antagonism and polarization.
      </p>
      <p>
        Cyber aggression, as a form of deviant behavior in the
Internet environment, was studied in detail in [
        <xref ref-type="bibr" rid="ref23 ref24 ref25 ref26 ref27 ref28">23-28</xref>
        ]. This
socio-psychological phenomenon has many forms, the main
of which are trolling, cybermobbing and astroturfing.
      </p>
      <p>As can be seen from the above review of published
scientific papers, the search for deviant communities is an
important task both for scientists involved in researching
such communities and for law enforcement agencies.
Unfortunately, most often, the identification of deviant
communities is carried out manually, often only by user
complaints.</p>
      <p>The aim of this work was to develop a methodology for
identifying deviant communities in the social network
Vkontakte in automatic mode. To achieve this goal, two
options have been proposed to search for such communities.</p>
    </sec>
    <sec id="sec-2">
      <title>II. RESULTS</title>
      <p>In the first version, the following algorithm for searching
for such communities is proposed and programmatically
implemented. For the studied community, the number l of
subscribers blocked by the social network for breaking the
rules, as well as the total number L of subscribers of this
community, is determined. The coefficient k  l is found. It
L
is assumed that if the coefficient k is greater than some
critical value kd, then the community under study is deviant.</p>
      <p>The software implementation of the above algorithm was
implemented in the Python programming language. During
the implementation of this program, 50,704 communities of
the Vkontakte social network were randomly selected. In
order to shorten an influence of statistical error, only
communities with 100 or more total subscribers were
selected from the general list. Due to system and API
limitation, communities with a few members were
considered. A coefficient was calculated for each of these
communities. Further, all communities were sorted in
descending order of magnitude of this coefficient. Table 1
presents the first 20 communities from the list.
deviant community is determined. It is assumed that a
sufficiently large number of communities from this list will
also be deviant. This algorithm was programmatically
implemented using the Python programming language.</p>
      <p>To test the performance of this program, the deviant
community “Mom Anarchy” was chosen with an
identification number of 177615404. This community is
engaged in popularizing the ideas of anarchism and has
32097 subscribers. The data processing time was 18 hours.
Followers of this community are also subscribed to 940512
other communities. All of them were sorted in descending
order by the number of users who are also subscribed to the
Mama Anarchy community. Table 2 presents the first 20
communities from this list.</p>
      <p>In order to prevent propaganda of deviant communities,
in this table and further in table 2, the identification number
of all such communities is replaced by the symbols “***”.</p>
      <p>As can be seen from this list, there is only one deviant
community in it (community under No. 17). This community
was classified as deviant due to the presence of pornographic
material in it.</p>
      <p>Thus, the hypothesis that the percentage of blocked users
in deviant communities is greater than in non-deviant
communities has not been experimentally confirmed.
Furthermore, it’s clear that some communities are abandoned
and they can contain a lot of banned users because of lack of
moderation and new subscribers. Other communities can be
related to advertising or temporary events. But they are still
not deviant despite the fact that social network Vkontakte has
special rules that restrict the creation of such communities as
communities with an inappropriate content.</p>
      <p>The second option for searching for deviant communities
is based on the following algorithm: One community is
found for which it is known for certain that it is deviant. For
this community, a list of subscribers is defined. Each of these
subscribers defines the communities to which it is
subscribed. For each of the communities in this list, the
number of subscribers who are also subscribers of the studied
***
91050183</p>
      <p>***
159146575
***
***
***
***
57846937
***
***
150550417
149094324
30316056
66678575
12353330
154168174
173556111</p>
      <p>***
133180305</p>
      <p>As can be seen from this table, out of 20 communities of
the presented list, 9 are deviant. The main reasons that these
communities are attributed to deviants are: propaganda of
violence, criticism of the existing constitutional system, and
the use of profanity. This results show us that algorithm
results should not be considered as final predictions but as an
assumption. Still results must be managed by special person
to make a conclusion about community content. The main
aim of this algorithm for now is to narrow the search for
deviant communities.</p>
      <p>Furthermore, this algorithm allows to consider
communities with bigger amount of subscribers. However, it
should be mentioned that API has a strong impact on
algorithms productivity. Therefore such systems have a
portability limitations. Nevertheless, the core idea of this
system is to show dependencies between blocked users
amount and community content.</p>
      <p>The scientific novelty of this work lies in the proposed
algorithm, which helps to identify deviant communities.
Despite the fact that current algorithm can only help us to
make suggestion about community content, there could be
ways to improve it by using extra algorithms and tools, such
as image recognition tools and text analyzer. Therefore,
holistic recognition system could be developed to make more
accurate predictions about deviant communities in social
networks with open API.</p>
    </sec>
    <sec id="sec-3">
      <title>III. CONCLUSION</title>
      <p>Thus, the second way of identifying deviant communities
is much more effective than the first. This technique for
identifying deviant communities in automatic mode can be
applied not only on the social network Vkontakte but also in
other social networks. We also note that the second method
can be applied not only to search for deviant communities,
but also when searching for communities related to the
studied community, for example, in marketing research. In
the case of such studies, it is possible to determine the
interests of community users and, accordingly, build a policy
to attract new users to this community.</p>
      <p>Another possible use of this method is to conduct an
advertising campaign of a certain community. In this case, as
the studied community, you can choose the community
whose advertising you want to conduct. Define a list of
communities associated with this community and place
advertising messages in these communities.</p>
      <p>
        It should also be noted that to search for deviant
communities, it may be useful to use machine learning
methods, such as, for example, artificial immune systems
[
        <xref ref-type="bibr" rid="ref29 ref30 ref31">29-31</xref>
        ] or convolutional neural networks [
        <xref ref-type="bibr" rid="ref32 ref33 ref34 ref35 ref36 ref37 ref38 ref39 ref40 ref41">32-41</xref>
        ]. However,
even when using machine learning, the method of identifying
deviant communities by the presence of common subscribers
between the studied community, and the community about
which it is known for certain that it is deviant will not lose its
relevance. This is primarily due to the fact that this method
has a high degree of transparency in interpreting the results
obtained, in contrast to machine learning methods, which are
often a black box, the results of which are often
incomprehensible.
      </p>
      <p>Thus, in this study, a new method is proposed that allows
you to quickly, cheaply and efficiently search for deviant
communities.</p>
    </sec>
    <sec id="sec-4">
      <title>ACKNOWLEDGMENT</title>
      <p>In conclusion, we would like to thank Marina
Vsevolodovna Glumova, Director of the Physico-technical
Institute of the V. I. Vernadsky Crimean Federal University,
and Victor Vasilyevich Milyukov, head of the Department of
computer engineering and modeling of the Physico-technical
Institute of the V. I. Vernadsky Crimean Federal University,
for their assistance in organizing research.</p>
    </sec>
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