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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Analysis of the personal information from social networks to solve the problems of criminology</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>E A Gambarova</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>V A Bakaev</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>N V Olinder</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>A V Blagov</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>M E Naumov</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Samara National Research University</institution>
          ,
          <addr-line>Moskovskoe Shosse 34, Samara, Russia, 443086</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <fpage>172</fpage>
      <lpage>178</lpage>
      <abstract>
        <p>The article discusses the need to use social networks in the cognitive activities of participants in the criminal process, and suggests that it is possible to use information obtained from social networks in the investigation of crimes. Two approaches are compared: expert and automated. The authors offer tools for data collection and analyzing personal data from social networks.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>An important condition for improving the effectiveness of combating modern crime is the continuous
improvement of theoretical and practical knowledge of the investigator, investigator and operative
worker on the use of modern technologies in the investigation of crimes, as well as the search for new
ways to collect information.</p>
      <p>
        For example, recently much attention has been paid to technical systems for face recognition
[
        <xref ref-type="bibr" rid="ref1 ref2 ref3">1,2,3</xref>
        ].
      </p>
      <p>The information is central to the cognitive activity of the investigator, so the search for ways to
obtain the information more quickly and fully is an important area in criminology. Great opportunities
for working with information are provided by the Internet, in particular, social media (social networks.</p>
      <p>
        At present, it is necessary to note the change in the approach of citizens to the methods and forms
of communication, information circulation, etc., partly due to the development of the global Internet,
the development of virtual relations. Communication via social networks and messengers is gaining
more and more momentum [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. The growing popularity of social media (social networking, instant
messengers, etc.) [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], the spread of "virtual" databases, online banking, cloud storage and other tools
used for more comfortable and fast communication and receipt (supply) of services leads not only to
the need for normative regulation of these relations, but also determines the creation of new
approaches to virtual space in criminology.
      </p>
      <p>
        The need to use information from social networks in the investigation says the current investigator
on particularly important cases of the Republic of Belarus, K. Yu.n. Yu. F. Kamenetsky [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. In his
dissertation "the methodology of the initial phase of the investigation of embezzlement by abuse of
official authority in the public sector", he writes that "Anticipation of action by the embezzler and his
corrupt ties directly linked to the analytical work to establish social and family ties to the looting, the
adoption of measures of preventive character. One of the effective ways of investigating the
investigator's activities, along with the classical measures, is the monitoring of social networks
available on the global computer network.
      </p>
      <p>This problem is typical not only for forensic and procedural science in the Russian Federation, but
also for other countries, as "virtualization" is an integral part of the globalization process taking place
around the world. According to Professor Volchetskaya T. S., the problems associated with virtual
space are particularly promising for scientific development. So some steps to forensic and procedural
knowledge of the process of virtualization for several years, Russian scientists Efimov V. Yu, Vekhov
V. B., Volchetskaya.S., Ishin A. M., Meshcheryakov V. A., Olander N. In. Smushkin A. B. etc. So,
Meshcheryakov V. A. one of the first in his work "bases of a technique of investigation of crimes in
computer information sphere" referred to "virtual tracks». Subsequently, the section "forensic study of
traces" was supplemented with scientific developments related to the study of nature, nature, species,
processes of formation, identification and consolidation of virtual traces in the conduct of individual
investigations.</p>
      <p>When planning certain investigative actions, the investigator is tasked with choosing the most
effective ways to achieve this goal. As a rule, one of the tasks of planning investigative actions is to
collect information that will help the investigator to choose the tactics of this or that investigative
action in the future. Due to the fact that the investigator does not always have a large amount of time
to search for information about the event of interest or personality, it is necessary to choose ways that
will help to reduce the time of obtaining information. It seems promising to use information from the
Internet, including the monitoring of social networks, when planning investigative actions, in
particular, interrogation.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Methods of social network data collection and processing</title>
      <p>
        In criminology, the organization of the investigation is necessary to quickly obtain reliable information
about a person or group of people. Efficiency, reliability and timeliness are key factors. Therefore, it
seems reasonable to develop the most effective technology of obtaining and processing information,
thus, present the necessary methodological and methodical issues related to the application of the tools
of the Internet (social networking, etc.), elaboration of algorithm of search and verification of
information. The process of constructing an algorithm for solving a professional problem, the result of
which is the allocation of stages of the data processing process, the formal definition of their content
and the order of their execution, the development of a template of actions and/or mental operations,
allows to optimize the search-cognitive, organizational and technological component of the active
interaction of the person conducting the investigation with the objects of the world associated with a
criminal event [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>The task of collecting the necessary information from social networks can be divided into data
collection, filtering, processing and subsequent analysis.</p>
      <p>The authors of the study set the task of collecting data of social networks expertly, as well as using
the developed software. In the first case, a group of experts was determined who systematically
searched for the necessary personal information without the use of additional automated services. In
the second case, the following approach was used.</p>
      <p>Based on the task, the developed software package implements the following functionality:
 analysis of all profiles of target social networks (Vkontakte, Twitter, Instagram, LinkedIn) in
order to save open information in the database;
 matching the profiles belonging to one person in the group;
 making assumptions about the user's income level.</p>
      <p>For the implementation of a software product, we used the following technology stack: Scala,
Python, PostgreSQL, ApacheStorm, CatBoost. This choice is due to the requirement for horizontal
scaling of the system.</p>
      <p>CatBoost is used to build a mathematical model that determines a person's income level by such
parameters as: gender, age, education, field of activity, position, city, family status.</p>
      <p>To search for a person's accounts in other social networks, we use a two-layer perseptron,
comparing profiles by name, nickname, email, etc.</p>
      <p>
        Primary data are collected as follows [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>At the first stage the system analyzes all users of social networks VKontakte, Twitter and
Instagram and groups them in the following rules:</p>
      <p>● in each group there are no more than one profile from each social network;
● all profiles in one group belong to one person.</p>
      <p>This problem is solved by means of a program framework of Apache Spark (in particular,
superstructures of Spark Streaming intended for stream data processing see fig. 1) and the broker of
messages RabbitMQ realizing delivery of basic data in Spark Streaming.</p>
      <p>Description of steps:
1. Adding of data from different sources in queue for later processing. Data represent a set of
couples (network_id, user_id) containing information on profiles which are required to be analyzed.</p>
      <p>2. RDD (Resilient Distributed Dataset) formation by a packing of the basic data which are in queue
for increase in productivity.</p>
      <p>3. RDD (mapping) conversion. For each couple (network_id, user_id) the algorithm finds and
groups profiles on other social networks, and also additional information on the person to whom
belongs the initial account. The algorithm is restarted for each found profile until all available
information on the user is found. As sources can be: the public information specified on the page of
the user (the status, contact information, entries in the film, etc.).</p>
      <p>4. Export of data retrieveds from RDD in queue for the subsequent saving.</p>
      <p>5. Saving results in NoSQL to the MongoDB database in the form of documents with structure, the
reflected in table 1.</p>
      <p>The speed of data processing makes about 120-130 profiles a second. For work the Microsoft
Azure A2 v2 virtual computer was used (2 kernels, 4 GB of RAM, 20 GB of SSD). Casual users of
social network VKontakte (1.000.000 profiles) were analyzed.</p>
      <p>Thus, if to assume that speeds of processing of profiles of VKontakte, Instagram and Twitter are
equal, we will receive an approximate assessment of time which will be required for the analysis of all
users of target social networks:</p>
      <p>( ) = 4∗108+61∗21008+13∗108 ≈ 5324ℎ ≈ 221, (1)
where n - the number of servers in a cluster with a similar configuration.</p>
      <p>In case of horizontal scaling of a cluster the linear dependence between the number of servers and
processing rate of profiles is watched.</p>
      <p>Example of the reference to the table: results of an experiment are reflected in table 1.
Name of the field
_id
vk_id
facebook_id
instagram_id
twitter_id
other</p>
      <sec id="sec-2-1">
        <title>Type</title>
        <p>ObjectId
Int32
Int64
Int64
Int64
Object</p>
        <p>The further task comes down to expansion of the received base by association of profiles by the
rules described earlier on which pages bek-links aren't specified other social networks.</p>
        <p>
          Data grouping is based on the analysis of common features [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ]. The following procedure applies:
        </p>
        <p>Construction of a full multi-column graph, which stores information about the profiles of social
networks and the potential that characterizes the probability of their belonging to one person.</p>
        <p>At the vertices of a graph contains information about the profile that is used when the comparison
is made.</p>
        <p>To compare two profiles, a multilayer neural network is used. The input network layer is fed with a
vector of dimension 12, which contains the following data:
 Name ↔ Name'
max(Name → Username', Name' → Username)
max(Name → E-mail', Name' → E-mail)
max(Name → Skype', Name' → Skype)</p>
      </sec>
      <sec id="sec-2-2">
        <title>Username ↔ Username'</title>
        <p>max(Username → E-mail', Username' → E-mail)</p>
      </sec>
      <sec id="sec-2-3">
        <title>Username ↔ Skype'</title>
        <p>max(Skype → Username', Skype' → Username)
max(Skype → E-mail', Skype' → E-mail)
E-mail ↔ E-mail'
Phone ↔ Phone'</p>
        <p>Website ↔ Website'
Next, it defines the fullness of occurrences of a in b:</p>
        <p>
          →  = 1 −  + (+) ∈ [
          <xref ref-type="bibr" rid="ref1">0,1</xref>
          ], (2)
where d – is the number of delete operations to convert a to b; r – number of replacement operations to
convert a to b; s - number of transposition operations to convert a to b; len(x) – function to calculate
the length of the argument.
        </p>
        <p>
          Comparison a and b:
∀ ∈ [1, 
( )],  ∈ [1, 
 ↔  =
( )] [ ,  ] = 1 − 

∑1 ( ( ) ( [),, ((  )])) ∈ [
          <xref ref-type="bibr" rid="ref1">0,1</xref>
          ],
        </p>
        <p>
          ( [ ], [ ]) ∈ [
          <xref ref-type="bibr" rid="ref1">0,1</xref>
          ],
 ( [ ])
(3)
where dist(a, b) - is a function that calculates the Damerau-Levenshtein distance [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] for lines a and b;
fit(i) - a function that returns the index of the word of the string b, put in accordance with the word
a[i].
        </p>
        <p>
          The comparison operation does not consider the word order. All the words in the source strings are
compared in pairs, and then, using the algorithm of Kuhn-Munkres [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], each word of a string a is
defined in accordance with the word line b so that the sum of the similarity for all pairs of words was
the maximum. Also, punctuation marks and other symbols (except letters and numbers) are not taken
into account.
        </p>
        <p>Training and control samples are collected on the basis of primary data. The size of the training
sample ~106 pairs.</p>
        <p>Next in the generated graph for each pair of shares the following sequence of actions is performed:
- edges are sorted in descending order of weights;
-edges whose weight is less than the threshold value are removed, or one of the incident vertices is
already connected to some vertex of the opposite fraction.</p>
        <p>The result of these transformations is a graph in which each component of connectivity is a group
of accounts from different social networks that belong to one person.</p>
        <p>Due to the fact that a person can belong to several communities at the same time, and if the same
group was formed in several communities, it can be assumed that the accounts of this group really
belong to one user.</p>
        <p>Regular expressions and Scala's built-in mechanism of working with CS-grammars are used to
parse contact information.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Results and discussions</title>
      <p>Using the method of expert data collection and processing of social networks, the following results
were obtained. The following experiment was conducted. The expert group (115 people), offered to
look for information about certain people (3 people) on the given parameters: the place of residence of
the person, the place of study of the person, joining the founders, the presence of property, the
presence of debts and fines, participation in trials, travel and business trips, leisure, family, close
friends.</p>
      <p>An important condition was that the participants of the experiment did not use special technical
means and looked for information only in open sources.</p>
      <p>As a result of the experiment, it was found that it is easy to find information about the city of
residence (67% of participants found), although the specific address was found only 5.7% of
participants. 79% of the participants were able to find the place of work and study. Joining the
founders, shareholders, the status of an individual entrepreneur, etc.found 22% of the participants of
the experiment, the availability of information about the property could find only 10% of the
participants. Less than 2% of the participants found debts, fines and loans, less than 1% found
participation in trials (as a party), more than half of the participants of the experiment could find travel
and business trips, 50.6% could find information about parents, 29.5% of the participants of the
experiment , about the spouses of more than half of the participants, 52.5%; about brothers and sisters,
19%, about friends, on average 20.9 % (see table 2).
The joining the founders, shareholders, having the
status of an individual entrepreneur
debts, fines, loans
The fact of participation in court proceedings (as a
party)
Travelling and business trip
The information about parents
The information about spouses
The information about brothers and sisters
The information about friends</p>
      <p>The percentage of participants in the
experiment who discovered the information
67
5,7
79
22
2
1
50,6
29,5
52,5
19
20, 9</p>
      <p>The search and processing of information (including the determination of its reliability also took an
average of two and a half hours).</p>
      <p>Thus, during the experiment, certain parameters ("beacons") were identified, which are freely
available in social networks and can be accessed by any user: address, place of residence, place of
study, places of rest, business trips, etc.</p>
      <p>On the one hand, the experiment showed how much information about the person is stored in social
networks, which is a negative factor, as the level of personal data protection is reduced (although these
data are placed by the subjects themselves – freely, at will). On the other hand, such "openness" of
information can help in the work of investigative bodies in the investigation of crimes. For example,
when collecting information about possible participants in organized crime groups, in preparation for
individual investigations (interrogation, confrontation) or in General, when planning the investigation
of certain types of crimes.</p>
      <p>In Russia, the use of social networks in the investigation and prevention of crimes is not
widespread. In order to find out the reason of such unpopularity of the use of social networks in the
investigation of crimes in the framework of the study, a survey of investigators of the Samara region
was conducted. The reasons for this are: the complexity of the search for information (76%), the
duration of time (34%), the difficulties of procedural registration of search and use of such information
(91 %).</p>
      <p>After analyzing the answers of investigators, we concluded that the reduction of time to search for
information, as well as the possibility of using some algorithms or software, could create conditions
for a wider use of social networks in the investigation of crimes. In this connection, it is advisable to
consider the following method of collecting information in the framework of the study.</p>
      <p>The second method using the developed software was obtained as follows. The created system of
creating portraits of users of social networks is able to collect the following data:
 user profile identifiers in other social networks (including if they are not explicitly specified on
their page);
 other contact information (phone numbers, email addresses, Skype logins);
 User’s name and nicknames;
 the date of birth;
 city of residence;
 relatives (parents, children, brothers, sisters);
 education (University, school);
 place of work and position;
 уровень дохода (using HeadHunter and Yandex.Work statistic services).</p>
      <p>As an experiment, the participants of the community "Big village" were analyzed
(https://vk.com/bigvill). For 197 seconds processed data 48.525 profiles Vkontakte (Instagram – 8734,
Twitter – 4367, LinkedIn – 1455).</p>
      <p>As a result, you can see that with the help of the software you can collect and process much more
information more quickly, while, of course, a more detailed analysis can be carried out expertly. The
developed software product can be used in criminology for operational preliminary analysis of
personal data, including for checking their reliability (for various parameters, for example, according
to the specified dates).</p>
      <p>Table 3 presents a comparative analysis of the two approaches: with the help of experts and with
the help of software.</p>
      <p>Table 3. The comparison of two approaches (expert and software).</p>
      <sec id="sec-3-1">
        <title>Expert The expenditures labor115experts, 2 hours</title>
      </sec>
      <sec id="sec-3-2">
        <title>The number ofthe social profiles. networks, processed data websites and other open sources</title>
      </sec>
      <sec id="sec-3-3">
        <title>Using the software</title>
      </sec>
      <sec id="sec-3-4">
        <title>The software for 1 PC, 197 seconds</title>
      </sec>
      <sec id="sec-3-5">
        <title>The profiles:VK – 48 525, Instagram – 8 734, Twitter – 4 367, LinkedIn – 1 455.</title>
        <p>The The high, including
completeness ofinformation about fines and
the information loans</p>
      </sec>
      <sec id="sec-3-6">
        <title>The average: - personal data, - contacts, - connections, - place of work and approximate income level</title>
        <p>In General, we can say that social networks can be considered to solve the problems of criminology
and serve as the object of research. On the one hand, openness and, as a consequence, availability of
data is a negative factor, as the level of personal data protection is reduced (although these data are
placed by the subjects themselves). On the other hand, such "openness" can help in the work of
investigative bodies in the investigation of crimes. For example, when collecting information about
possible participants of criminal groups, when preparing for certain investigative actions (for example,
interrogation, confrontation) or in General, when planning the investigation of certain types of crimes.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Conclusions</title>
      <p>The result of the work is the study and comparison of methods of collection and processing of
personal data of users of social networks to solve the problems of criminology. It was found that using
social networks you can find a lot of information that users about themselves, their relatives, their
work and studies leave on their own, some information is left about users by other users, for example
by posting joint photos, videos. These circumstances together make it possible to make a fairly
detailed dossier on active users of social networks, which may be important for the investigator, and
the information obtained can provide significant assistance in the investigation of crimes.
It is obvious that the comparison of performance and quality of information received by man and
machine, gives a predictable result. However, the use of such software by law enforcement agencies
can significantly reduce the time to search for basic information and discard from the sample of people
who do not meet the specified criteria. And then additional information can be collected by expert.</p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>The work has been performed with partial financial support from the Ministry of Education and
Sciences of the Russian Federation within the framework of implementation of the Program for
Improving the Samara University Competitiveness among the World's Leading Research and
Educational Centers for the Period of 2013-2020s.</p>
    </sec>
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