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 <front>
  <journal-meta>
   <journal-id journal-id-type="publisher-id">Russian Journal of Earth Sciences</journal-id>
   <journal-title-group>
    <journal-title xml:lang="en">Russian Journal of Earth Sciences</journal-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Russian Journal of Earth Sciences</trans-title>
    </trans-title-group>
   </journal-title-group>
   <issn publication-format="online">1681-1208</issn>
  </journal-meta>
  <article-meta>
   <article-id pub-id-type="publisher-id">57849</article-id>
   <article-id pub-id-type="doi">10.2205/2023ES000839</article-id>
   <article-categories>
    <subj-group subj-group-type="toc-heading" xml:lang="ru">
     <subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject>
    </subj-group>
    <subj-group subj-group-type="toc-heading" xml:lang="en">
     <subject>ORIGINAL ARTICLES</subject>
    </subj-group>
    <subj-group>
     <subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject>
    </subj-group>
   </article-categories>
   <title-group>
    <article-title xml:lang="en">COVID-19 Pandemic Course 2020–2022: Description by Methods of Mathematical Statistics and Discrete Mathematical Analysis</article-title>
    <trans-title-group xml:lang="ru">
     <trans-title>COVID-19 Pandemic Course 2020–2022: Description by Methods of Mathematical Statistics and Discrete Mathematical Analysis</trans-title>
    </trans-title-group>
   </title-group>
   <contrib-group content-type="authors">
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-4874-7475</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Гвишиани</surname>
       <given-names>Алексей Джерменович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Gvishiani</surname>
       <given-names>Alexei D.</given-names>
      </name>
     </name-alternatives>
     <email>rjes@wdcb.ru</email>
     <bio xml:lang="ru">
      <p>доктор физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>doctor of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-1"/>
     <xref ref-type="aff" rid="aff-2"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5037-4778</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Одинцова</surname>
       <given-names>Анастасия Александровна</given-names>
      </name>
      <name xml:lang="en">
       <surname>Odintsova</surname>
       <given-names>Anastasia Aleksandrovna</given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-3"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Ровенская</surname>
       <given-names>Елена Александровна</given-names>
      </name>
      <name xml:lang="en">
       <surname>Rovenskaya</surname>
       <given-names>Elena Aleksandrovna</given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-4"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Boyarshinov</surname>
       <given-names>Grigory </given-names>
      </name>
      <name xml:lang="en">
       <surname>Boyarshinov</surname>
       <given-names>Grigory </given-names>
      </name>
     </name-alternatives>
     <email>g.boyarshinov@gcras.ru</email>
     <xref ref-type="aff" rid="aff-5"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Белов</surname>
       <given-names>Иван Олегович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Belov</surname>
       <given-names>Ivan Olegovich</given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-3"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-6930-3331</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Добровольский</surname>
       <given-names>Михаил Николаевич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Dobrovolsky</surname>
       <given-names>Michael Nikolaevich</given-names>
      </name>
     </name-alternatives>
     <email>m.dobrovolsky@gcras.ru</email>
     <xref ref-type="aff" rid="aff-3"/>
    </contrib>
   </contrib-group>
   <aff-alternatives id="aff-1">
    <aff>
     <institution xml:lang="ru">Геофизический центр Российской Академии Наук</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Geophysical Center of the Russian Academy of Sciences</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-2">
    <aff>
     <institution xml:lang="ru">Институт физики Земли им. О.Ю. Шмидта Российской академии наук</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Schmidt Institute of the Physics of the Earth Russian Academy of Sciencies</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-3">
    <aff>
     <institution xml:lang="ru">Геофизический центр Российской Академии Наук</institution>
     <country>RU</country>
    </aff>
    <aff>
     <institution xml:lang="en">Geophysical Center of the Russian Academy of Sciences</institution>
     <country>RU</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-4">
    <aff>
     <institution xml:lang="ru">Международный институт прикладного системного анализа (МИПСА)</institution>
     <country>Австрия</country>
    </aff>
    <aff>
     <institution xml:lang="en">International Institute for Applied Systems Analysis (IIASA)</institution>
     <country>Austria</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-5">
    <aff>
     <institution xml:lang="ru">ГЦ РАН</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">GC RAS</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <pub-date publication-format="print" date-type="pub" iso-8601-date="2023-06-29T00:00:00+03:00">
    <day>29</day>
    <month>06</month>
    <year>2023</year>
   </pub-date>
   <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2023-06-29T00:00:00+03:00">
    <day>29</day>
    <month>06</month>
    <year>2023</year>
   </pub-date>
   <volume>23</volume>
   <issue>2</issue>
   <fpage>1</fpage>
   <lpage>20</lpage>
   <history>
    <date date-type="received" iso-8601-date="2023-03-22T00:00:00+03:00">
     <day>22</day>
     <month>03</month>
     <year>2023</year>
    </date>
    <date date-type="accepted" iso-8601-date="2023-05-29T00:00:00+03:00">
     <day>29</day>
     <month>05</month>
     <year>2023</year>
    </date>
   </history>
   <self-uri xlink:href="https://rjes.ru/en/nauka/article/57849/view">https://rjes.ru/en/nauka/article/57849/view</self-uri>
   <abstract xml:lang="ru">
    <p>The paper describes the course of the COVID-19 pandemic using a combination of mathematical statistics and discrete mathematical analysis (DMA) methods. The method of regression derivatives and FCARS algorithm as components of DMA will be for the first time tested outside of geophysics problems. The algorithm is applied to time series of the number of new cases of COVID-19 infections per day for some regions of Russia and the Republic of Austria. This allowed to assess the nature and anomalies of pandemic spread as well as restrictive measures and decisions taken in terms of the administration of countries and territories. It was shown that these methods can be used to identify time intervals of change in the nature of the incidence rate and areas with the most severe course of the epidemic. This made it possible to identify the most significant restrictive measures that allowed to reduce the growth of the disease.</p>
   </abstract>
   <trans-abstract xml:lang="en">
    <p>The paper describes the course of the COVID-19 pandemic using a combination of mathematical statistics and discrete mathematical analysis (DMA) methods. The method of regression derivatives and FCARS algorithm as components of DMA will be for the first time tested outside of geophysics problems. The algorithm is applied to time series of the number of new cases of COVID-19 infections per day for some regions of Russia and the Republic of Austria. This allowed to assess the nature and anomalies of pandemic spread as well as restrictive measures and decisions taken in terms of the administration of countries and territories. It was shown that these methods can be used to identify time intervals of change in the nature of the incidence rate and areas with the most severe course of the epidemic. This made it possible to identify the most significant restrictive measures that allowed to reduce the growth of the disease.</p>
   </trans-abstract>
   <kwd-group xml:lang="en">
    <kwd>COVID-19</kwd>
    <kwd>DMA</kwd>
    <kwd>statistics</kwd>
    <kwd>data analysis</kwd>
   </kwd-group>
   <funding-group>
    <funding-statement xml:lang="en">This work was supported by the Russian Foundation for Basic Research (project No. 20-57-82003 “System Analysis of patterns of COVID-19 spread in Europe and Russia”).</funding-statement>
   </funding-group>
  </article-meta>
 </front>
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