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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">ecr-journal</journal-id><journal-title-group><journal-title xml:lang="ru">Экономическая наука современной России</journal-title><trans-title-group xml:lang="en"><trans-title>Economics of Contemporary Russia</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1609-1442</issn><issn pub-type="epub">2618-8996</issn><publisher><publisher-name>Regional Public Organization for Assistance to the Development of Institutions of the Department of Economics of the Russian Academy of Sciences</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.33293/1609-1442-2020-1(88)-109-127</article-id><article-id custom-type="elpub" pub-id-type="custom">ecr-journal-461</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ЭКОНОМИЧЕСКАЯ ПОЛИТИКА И ХОЗЯЙСТВЕННАЯ ПРАКТИКА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ECONOMICAL POLICY AND ECONOMICAL PRACTICE</subject></subj-group></article-categories><title-group><article-title>Обнаружение признаков горизонтального сговора при государственных закупках с использованием методов машинного обучения</article-title><trans-title-group xml:lang="en"><trans-title>Detecting Indicators of Horizontal Collusion in Public Procurement with Machine Learning Methods</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8130-1259</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Молчанова</surname><given-names>Глафира Олеговна</given-names></name><name name-style="western" xml:lang="en"><surname>Molchanova</surname><given-names>Glafira O.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Лаборатория анализа данных и отраслевой динамики ИОРИ, младший научный сотрудник, SPIN-код 2699-3804</p></bio><bio xml:lang="en"><p>Junior researcher at the laboratory for data analysis and industry dynamics, Institute for Industrial Economics</p></bio><email xlink:type="simple">molchanova-go@ranepa.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8207-1790</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Рей</surname><given-names>Алексей Игоревич</given-names></name><name name-style="western" xml:lang="en"><surname>Rey</surname><given-names>Alexey I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Лаборатория анализа данных и отраслевой динамики ИОРИ, заведующий, SPIN-код 3955-2904</p></bio><bio xml:lang="en"><p>Cand.Econ.Sci., Head of laboratory for data analysis and industry dynamics, Institute for Industrial Economics</p></bio><email xlink:type="simple">rey-ai@ranepa.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-6544-5359</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шагаров</surname><given-names>Дмитрий Юрьевич</given-names></name><name name-style="western" xml:lang="en"><surname>Shagarov</surname><given-names>Dmitry Yu.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Лаборатория анализа данных и отраслевой динамики ИОРИ, младший научный сотрудник</p></bio><bio xml:lang="en"><p>Junior researcher at the laboratory for data analysis and industry dynamics, Institute for Industrial Economics</p></bio><email xlink:type="simple">shagarov-dy@ranepa.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Российская академия народного хозяйства и государственной службы при Президенте РФ, Москва</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Russian Presidential Academy of National Economy and Public Administration, Moscow</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2020</year></pub-date><pub-date pub-type="epub"><day>05</day><month>04</month><year>2020</year></pub-date><volume>0</volume><issue>1</issue><fpage>109</fpage><lpage>127</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Молчанова Г.О., Рей А.И., Шагаров Д.Ю., 2020</copyright-statement><copyright-year>2020</copyright-year><copyright-holder xml:lang="ru">Молчанова Г.О., Рей А.И., Шагаров Д.Ю.</copyright-holder><copyright-holder xml:lang="en">Molchanova G.O., Rey A.I., Shagarov D.Y.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.ecr-journal.ru/jour/article/view/461">https://www.ecr-journal.ru/jour/article/view/461</self-uri><abstract><p>Совершенствование закупочных процедур и их цифровизация помогают предотвращать и выявлять картели, но в то же время приводят к появлению новых антиконкурентных схем поведения. В нашем исследовании мы концентрируем внимание на электронных аукционах, которые стали в последние годы основным способом осуществления государственных закупок в России. Тот факт, что электронные аукционы дают доступ к большему числу крупных государственных заказов, усиливает стимулы участников торгов заключать антиконкурентные соглашения. Поэтому улучшение методов выявления картелей на электронных аукционах становится особенно актуальной проблемой. Цель данной работы состояла в разработке метода для обнаружения признаков горизонтального сговора на торгах. С помощью методов машинного обучения мы тренируем классификаторы, которые предсказывают наличие или отсутствие картеля в электронных аукционах в зависимости от распределения ставок участников аукциона, времени подачи заявок, длительности проведения торгов и числа участников. Переменные для модели были отобраны на основании графиков распределений, построенных для выборки по картелям и случайной выборки. Исследование проводится на основе данных с сайта государственных закупок и информации о сговорах на торгах из дел Федеральной антимонопольной службы (ФАС). Результаты показали, что модель случайного леса наиболее точно предсказывает выявление картеля на электронном аукционе. Правильность предсказания – 84%, а полнота и точность модели – 83 и 87%. Наиболее значимыми для классификации переменными оказались уровень снижения цены, разница во времени подачи заявок и начальная (максимальная) цена контракта.</p></abstract><trans-abstract xml:lang="en"><p>Improvement of procurement procedures and their digitization help prevent and identify cartels, but at the same time lead to the emergence of new anticompetitive schemes. In this paper we focus on electronic auctions, which have become the main method of public procurement in Russia in recent years. As e-auctions provide access to many big government orders; the incentives for bidders to join anti-competitive agreements are increased. Therefore, the development of methods to detect bid rigging at electronic auctions is of high practical importance. The aim of this work was to develop a method for detecting signs of horizontal collusion at an auction. We use machine learning methods to train classifiers that predict the presence or absence of cartel in electronic auctions, depending on the distribution of bidders, the time of submission of applications, the duration of the auction and the number of participants. Variables for the model were selected on the basis of distribution plots built for sample of cartels and random sample. The study is based on data from public procurement Web portal and the information about bid rigging from cases of the Federal Antimonopoly Service. The results showed that the Random forest model most accurately predicts the detection of the cartels on electronic auctions. The accuracy of the prediction is 84%, and the recall and precision of the model are 83 and 87%, respectively. The most significant variables for the classification are the level of price reduction, the difference in the time of application filing of participants and the value of the maximum starting price of contract.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>выявление картелей</kwd><kwd>сговоры на торгах</kwd><kwd>государственные закупки</kwd><kwd>машинное обучение</kwd></kwd-group><kwd-group xml:lang="en"><kwd>detecting cartels</kwd><kwd>bid rigging</kwd><kwd>procurement auctions</kwd><kwd>screening methods</kwd><kwd>machine learning</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Abrantes-Metz R.M., Froeb L. M., Geweke J. F., Taylor C. T. A variance screen for collusion // International Journal of Industrial Organization. 2006. No. 24. P. 467–486.</mixed-citation><mixed-citation xml:lang="en">Abrantes-Metz R.M., Froeb L.M., Geweke J.F., Taylor C.T. (2006). 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