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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Determining  Reasons  of  Political  Rating  Changes  Based  on  Twitter Data </article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Taras Rudnyk</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Oleg Chertov</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute"</institution>
          ,
          <addr-line>37, Peremohy ave., Kyiv, 03056</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <fpage>36</fpage>
      <lpage>45</lpage>
      <abstract>
        <p>   This paper presents the results of a study on determining the rating of politicians based on a dataset collected from Twitter, comparing it with opinion polls. It is shown in the example of the analysis of the rating of the President of Ukraine Volodymyr Zelenskyy for the period from January 2019 to March 2021 that the differences in the rating can reveal events that influenced its change. Based on the specific reasons for the drop in rating, you can provide recommendations on how to stop the drop. On the other hand, the search for rating growth reasons can be used to determine the ways of increasing the respective politician's rating. To avoid misleading information and to verify the accuracy, detected Twitter events were compared to Google Trends and their consistency was confirmed.</p>
      </abstract>
      <kwd-group>
        <kwd> 1  political rating</kwd>
        <kwd>sociological polls</kwd>
        <kwd>Twitter</kwd>
        <kwd>natural language processing</kwd>
        <kwd>statistics</kwd>
        <kwd>Google Trend</kwd>
        <kwd>Ukraine</kwd>
        <kwd>Volodymyr Zelenskyy</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction </title>
      <p>Politicians are carefully considering the ratings. A lot of money is spent on sociological polls. Their
implementation requires the involvement of various specialists and institutes that conduct thorough
research, spending a lot of time on it. But times are changing. The massive diffusion of social networks
provides opportunities for researching electoral preferences of different categories of potential voters.
An automated algorithm could significantly reduce the time, money and number of people involved in
sociological polls.</p>
      <p>Such polls often make it difficult to understand which events have affected the rise or fall of the
rating. If the poll is conducted once a month, then during this period there are usually many events.
Which of these events had a decisive influence on the opinion of a particular respondent can only be
known if the authors of the poll have provided a corresponding specific question on such an event or a
group of relevant events.</p>
      <p>By researching social media data, it could be aggregated for different periods, it can be a month, a
week, a day or even an hour. Statistical counting of the number of messages on the social network will
provide important information, indicating which topics are most discussed. This responsiveness and
flexibility allow us to highlight key events and recommend how to respond to them to improve society’s
response.</p>
      <p>In this paper, we present the challenges and solutions in the following structure. Section 2 contains
the literature review on topics like our study. Section 3 explains the approach to determining the
political rating and the reasons for its changes. Section 4 presents the experiment, results, and
discussion. The outcome is compared with sociological polls and Google Trends. Section 5 contains
conclusions and future work.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Literature review </title>
      <p>
        Perhaps, Walter Lippmann was the first to theoretically substantiate the influence of the classical
mass media (press, radio, cinema, or, inferentially, television) on the political preferences of citizens
back in 1922 [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Both classical and modern studies show that the media both influence the voters’
preferences during elections [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] and produce more long-term effects: they influence the formation of a
stable vision about parties [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], the formation of political coalitions after elections [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], etc.
      </p>
      <p>
        The idea of using social networks to calculate political ratings also is not new. Interestingly, the first
studies of this kind (see, for example, [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]) showed a low correlation between a politician's involvement
in online activity and her/his rating. This result was obtained when analyzing the impact of social media
on the US presidential election in 2012. But already in the next election in 2016, almost all experts
associated the victory of Donald Trump, in particular, with his great activity on Twitter [
        <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
        ]. Burnap
et al. [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] sought to predict in advance the results of the general election in the UK in 2015, based on the
recognition that “more tweets - more votes”. Tumasjan et al. [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], based on the analysis of the elections,
made almost the same conclusion, but they analyzed not only the number of tweets but also carried out
their content-analysis of over 100,000 messages containing a reference to either a political party or a
politician. Anuta et al. [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] conducted a sentiment analysis to see if social media could pave the way
for less biased results than regular polls. Their findings suggest that, although numerical shifts are
common in both approaches, using only social media for predictions may lead to less accurate
predictions. Cameron et al. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] explored whether a candidate’s online presence could affect his chances
of being elected. Using two regression models, they concluded that there is statistical, albeit small,
significance between the number of people who follow or be friends with a politician on social media
and the election results.
      </p>
      <p>
        Researchers often use such popular social network as Facebook. Stephen R. Neely in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] considers
politically motivated unfriending or unfollowing on Facebook in the lead-up to the 2020 USA
Presidential election. But due to several restrictions, it is much harder to collect data from this social
network than from Twitter. It is Twitter that provides access to some data about its users and their
actions, which potentially allows drawing reasonable conclusions about their electoral preferences.
      </p>
      <p>
        The vast majority of articles that explore the relationship between the popularity of a politician or
some political force and their social activity or the activity of their supporters/opponents in online social
networks are based on an analysis of a snapshot of relevant messages. The first article in which such an
analysis is done based on data collected over four years was published only last year [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. Therefore,
studies that operate with real data collected over a sufficiently long period (from six months), which
allows you to accumulate and highlight the factors that characterize the electoral prospects of a certain
politician, are of particular interest.
      </p>
      <p>
        In social networks, users can act alone and even unite into groups. In [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] the approach to detect
groups of phony accounts on Facebook was introduced. Chronological analysis of user messages
allowed us to detect those who tried to influence other group members. Analyzing the electoral
prospects of a particular political leader, it is advisable to study, first of all, the dynamics of change in
that part of voters who unite around their leader in a social network group [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. There are three main
types of human bias that are manifested in social networks [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]: a tendency to support the opinion of
an authority figure, filtering out only those events that confirm previous beliefs or values, moreover,
events that contradict a person's opinion only increase her/his confidence in her/his rightness. It is
obvious that a certain political force or a specific political leader, explicitly or implicitly, forms various
support groups in social networks, through which they exert their influence both on their supporters and
on the general mass of voters.
      </p>
      <p>Objectives: This study sets in a certain sense the inverse problem and it intends (i) to confirm the
possibility, based on the activity of some users of a social network during a sufficiently long period
(from six months), to determine how popular this or that political force is in the electoral sense, and (ii)
to find out and analyze: is it then possible to identify the events that led to a change in the corresponding
political rating?
3. Approach to determining the political rating and the reasons for its changes  </p>
      <p>
        To determine the political rating of Ukrainian President Volodymyr Zelenskyy, the Twitter dataset
from our previous research [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] was used. We have made a few changes compared to our previous
article that has improved the calculated rating by 4%. The number of subscribers was no longer
considered to find opinion leaders. It has been found that many accounts have so-called “dead”
subscribers who were once registered but have not been active for a long time. These accounts can be
old bots or just people who have stopped using Twitter. Most of these subscribers were seen on pages
of politicians who have been in politics for a long time but did not win the latest election. For example,
the page of the former Prime Minister of Ukraine – Arseniy Yatsenyuk. At the same time, some bloggers
have relatively few subscribers, but almost all of them are active – like, retweet and comment on tweets.
For example, the page of Sergei Sternenko.
      </p>
      <p>
        Another improvement in the formula was the greater importance of retweets compared to likes.
Therefore, we multiply them by an empirically selected coefficient equal to 2. The same multiplier for
retweets was used by researchers of Donald Trump’s activity in [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. The following is the final formula
for subscriber activity calculation:
followers  2 ∗    (1) 
 
      </p>
      <p>The next important change in the formula is the use of the sum of the natural logarithms of each
component instead of the product. This change allowed us to consider all the terms separately and apply
the coefficient equal to 4 so that the influence of the account was not dominant compared to the other
two terms. The coefficient was chosen empirically to obtain the best result. Since the tweet score can
be less than one, instead of the usual logarithm we use the logarithm of 1 + tweet score.
 log
1 
log
log
4
 
(2) </p>
      <p>To detect dates of opinion changes the data is arranged into shorter periods. Initially to weeks. Once
the algorithm detects the week with anomaly rating changes – rapid growth or decline of the chart, then
the weeks are split by days. For each period rating changes, which may be not only one day but several
days in a row, statistics of the most common words were collected. For each word, except for stop
words (a set of commonly used words in any language), a number of occurrences in popular news got
calculated. The words which occurred in the news the most were called keywords and got stored as
potentially important in terms of political rating impact. To avoid false keywords selected in the
previous step they could be double-checked in Google trends. Once the dates of tweets and Google
Trends fit then specific news that affected the rating received. On some dates, the political rating may
be affected not only by one event. Sometimes ratings changed after several positive or negative news.
Therefore, it is important to collect all popular news.</p>
    </sec>
    <sec id="sec-3">
      <title>4. Experiment, Results and Discussion   4.1. Volodymyr Zelenskyy’s political rating compared to a sociological poll </title>
      <p>The new approach allowed us to achieve results 4% better than with the original formula. The total
deviation of the rating is 16%. Calculated ratings from Twitter data and sociological poll results are
presented in Figure 1. Black bars represent the results of the algorithm, and the dashed grey line shows
sociological polls’ result2.</p>
      <p>2 https://ratinggroup.ua/files/ratinggroup/reg_files/rg_ukraine_covid_cati_ix_wave_022021_press.pdf</p>
      <sec id="sec-3-1">
        <title>Figure 1: Volodymyr Zelenskyy support difference by date aggregated monthly </title>
        <p>4.2.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Identification of the reasons for the rating fall </title>
      <p>To recognize the reasons for the fall in rating, data aggregation was carried out not by months, but
by weeks. The first detected drop in the rating is a consequence of the beginning of the COVID-19
epidemic in Ukraine. Many people became ill, and on March 25th in the year 2020, the Cabinet of
Ministers of Ukraine imposed a 30-day state of emergency across the country due to the spread of
coronavirus disease. Examples of tweets with negative scores for observed dates are presented in
Table 1. Calculated by proposed model rating changes for this period are presented in Figure 2.
Table 1 </p>
      <sec id="sec-4-1">
        <title>Negative tweets related to COVID‐19 at the end of March in Ukraine </title>
      </sec>
      <sec id="sec-4-2">
        <title>Created at  2020‐03‐21 19:39:44  2020‐03‐27 10:52:57  2020‐04‐05 17:14:49 </title>
      </sec>
      <sec id="sec-4-3">
        <title>Text </title>
      </sec>
      <sec id="sec-4-4">
        <title>A state of emergency has been declared in Kharkiv Oblast  due to the COVID‐19 pandemic. </title>
      </sec>
      <sec id="sec-4-5">
        <title>To see on the screen the inaction of the authorities to  prepare for the coronavirus is extremely saddening and  indignant. </title>
      </sec>
      <sec id="sec-4-6">
        <title>We are filing a lawsuit against the absolutely illegal </title>
        <p>decision of the Cabinet of Ministers, by which he actually 
introduced a state of emergency in the country, bypassing 
the President and the Verkhovna Rada. No "good 
intentions" can be the basis for violating the Constitution 
of Ukraine. </p>
      </sec>
      <sec id="sec-4-7">
        <title>Score  ‐3  ‐5  ‐2 </title>
      </sec>
      <sec id="sec-4-8">
        <title>Figure  2:  Volodymyr  Zelenskyy  rating  from  02.03.2020  to  20.04.2020  calculated  by  the  proposed </title>
        <p>model </p>
        <p>Another rating loss was detected when on July 14, 2020, the Council legalized the gambling
business. Rating changes for this period are presented in Figure 3.
4.3.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Identification of the reasons for the rating growth </title>
      <p>To recognize the reasons for the growth of rating, data aggregation was carried out not by months
or weeks, but by days. The first detected growth of rating started on the 25th of January year 2021 and
exposed interesting reasons on how algorithms could be improved. Volodymyr Zelenskyy was born on
the 25th of January and received on that date and a few days after a lot of good congratulatory words.
Our algorithms accidentally detected such behavior as the rating grows. To improve the proposed
approach, the major dates from personal politician life such as birthdays, marriage or family
celebrations should be removed.</p>
      <p>The next rating growth was detected on the 2nd of February year 2021. On that date, The President
of Ukraine Volodymyr Zelenskyy put into effect the decision of the National Security and Defense
Council on the application of sanctions against the People’s Deputy Taras Kozak and the TV channels
112 Ukraine, NewsOne and ZIK, which were blocked. The deputy and his TV channels carried out
antiUkrainian activities.</p>
      <p>The last rating growth was detected on the 16th of February year 2021. This one is interesting
because is a result of multiple news on the same date which is alone not so powerful as the previous
one but gives a significant growth as an aggregated result. On that date:
 Volodymyr Zelenskyy had an official visit to the United Arab Emirates and agreed on
agreements and memoranda worth more than three billion dollars, cooperation in various fields,
from defense to agriculture, foreign direct investment in Ukraine and readiness to increase interstate
trade several times. Examples of tweets related to this news are presented in the first two rows of
Table 2;
 Volodymyr Zelenskyy announced the reduction of the powers of the Kyiv District
Administrative Court. An example of a tweet related to the announcement is presented in the third
row of Table 2;
 The speaker of parliament Dmitry Razumkov said that deputies will start to be left without
mandates for “button-pressing”. An example of a tweet related to the speaker’s words is presented
in the fourth row of Table 2.
 
Table 2 </p>
      <sec id="sec-5-1">
        <title>Examples of tweets with a positive score </title>
      </sec>
      <sec id="sec-5-2">
        <title>Created at </title>
        <p>2021‐0‐15 13:47:18 
2021‐02‐14 18:44:28 
2021‐02‐13 16:35:01 
2021‐02‐13 10:29:44 </p>
      </sec>
      <sec id="sec-5-3">
        <title>Text </title>
      </sec>
      <sec id="sec-5-4">
        <title>During the official visit of the President of Ukraine </title>
      </sec>
      <sec id="sec-5-5">
        <title>Volodymyr Zelenskyy to the United Arab Emirates, the </title>
      </sec>
      <sec id="sec-5-6">
        <title>Ukrainian delegation signed several bilateral documents. </title>
      </sec>
      <sec id="sec-5-7">
        <title>Olena Zelenska suggested intensifying cultural </title>
        <p>cooperation with the UAE. Among the initiatives are 
weeks of Ukrainian cinema and days of folk art in the </p>
      </sec>
      <sec id="sec-5-8">
        <title>Emirates. </title>
      </sec>
      <sec id="sec-5-9">
        <title>Zelenskyy announced the reduction of the powers of the </title>
      </sec>
      <sec id="sec-5-10">
        <title>Kyiv District Administrative Court. </title>
      </sec>
      <sec id="sec-5-11">
        <title>Razumkov said that the deputies will lose their mandates  due to button‐pressing </title>
      </sec>
      <sec id="sec-5-12">
        <title>Score  4  3  1 </title>
        <p>4 </p>
        <p>When several news items fall upon the same date, it is important to understand how much each of
them affected the result. To do this, we calculated the statistics of the frequency of news data. The
results in Figure 5 show that the news about the United Arab Emirates was much more resonant than
the other two.</p>
        <p>Google Trends could be used to verify that the right news is selected. This tool will allow checking
which news has been popular in each period and whether it coincides with the results obtained based
on data from Twitter. Figures 6-8 show that news detected by an algorithm using Twitter data fell on
the same dates as they appeared in google search in Ukraine. Some news could start one or two days
earlier than got discussed on Twitter. The administrative court and button-pressing are highly
discussable topics in Ukraine, even if they were not the absolute maximum on the 14th of February they
were still on the local maximum.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>5. Conclusion and Future work </title>
      <p>The conducted research proposed several algorithms to determine the rating of politicians, detect
dates when news affected ratings the most and identify specific news which influenced grows or fall of
the rating. Experimental results conducted on Ukrainian President Volodymyr Zelenskyy’s page on
Twitter show that the proposed approach allows not only to detect of ratings and their changes but detect
news that influenced such changes the most.</p>
      <p>The result is slightly different from sociological polls. There are several explanations for this:
 Twitter is not very popular in Ukraine;
 Not all segments of the population participating in the elections use this social network.</p>
      <p>For example, there are very few elderly people;
 Twitter is used by people who do not yet have the right to vote ― minors.</p>
      <p>In future work proposed model will be evaluated on a calculation of political rating for French
elections candidates – Emmanuel Macron and Marine Le Pen. The conducted research confirms that it
is possible to identify the events that led to a change in the corresponding political rating. In future
work, we plan to develop a system of recommendations for politicians or commercial brands based on
the identified key events on how to react to news or informational attacks in order to avoid or decrease
the loss of rating.</p>
    </sec>
    <sec id="sec-7">
      <title>6. References </title>
    </sec>
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