politscienceПолитическая наукаPolitical science1998-1775ИНИОН РАН10.31249/poln/2026.01.03politscience-1280Research ArticleСОСТОЯНИЕ ДИСЦИПЛИНЫДвухпартийность в электоральных исследованиях: количественные индикаторыTwo-partyism in electoral studies: empirical indicatorshttps://orcid.org/0000-0001-9769-9230ГолосовГ. В.GolosovG. V.

Голосов Григорий Васильевич - доктор политических наук, ведущий научный сотрудник.

Санкт-Петербург

Grigorii V. Golosov.

St. Petersburg

ggolosov@gmail.comЕвропейский университет в Санкт-ПетербургеРоссияEuropean University at St. PetersburgRussian Federation20261503202601Изменения в электоральном ландшафте: структурные и институциональные факторы4264Copyright © Голосов Г.В., 20262026Голосов Г.В.Golosov G.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.politnauka.ru/jour/article/view/1280

В силу их практической и теоретической важности, двухпартийные конфигурации занимают важное место в электоральных исследованиях. Однако в эмпирическом кросс-национальном анализе измерение двухпартийности часто подменяется измерением концентрации / фрагментации партийной системы, что приводит к нежелательным потерям информации. В этом исследовании дается обзор двух мер двухпартийности, уже предложенных, хотя и редко используемых, в политологии, и предлагается новый индикатор, который прозрачен в своем математическом строении и удовлетворяет теоретическим требованиям, которые должны выполняться при измерении двухпартийности. Свойства индексов, как старых, так и новых, тестируются на гипотетическом наборе данных, включающем партийные конфигурации с широко варьирующимися структурными характеристиками, и на реальном наборе данных, охватывающем выборы, проведенные в 75 странах мира в 2001–2023 гг. Анализ показывает полезность нового индекса в сравнительных исследованиях, одновременно подтверждая валидность ранее разработанных мер. Новый индекс удовлетворяет всем критериям, которые могут применяться к мерам двухпартийности, как теоретически, так и с перспективы исследовательской практики. Поэтому он может служить полезным дополнением к инструментарию политических исследований. Важно и то, что требования к полноте данных, предъявляемые новым методом измерения, абсолютно минимальны. Это позволяет использовать его для анализа исторической электоральной статистики, когда все доступные результаты выборов сводятся к долям голосов или мест, полученных двумя крупнейшими партиями.

Due to their practical and theoretical significance, two-party configurations are important in electoral studies. However, in empirical cross-national analysis, the measurement of two-partyism is often substituted with measures of party system concentration or fragmentation, leading to undesirable information losses. This study overviews the existing measures of two-partyism that had been previously proposed, albeit rarely used, in political science, and introduces a new indicator that is transparent in its mathematical formula and fulfills theoretical requirements for measuring two-partyism. The properties of both existing and new indices are tested on a hypothetical dataset encompassing party configurations with widely varying structural characteristics, as well as on a real dataset covering elections held in 75 countries worldwide in 2001–2023. The analysis demonstrates the utility of the new index in comparative research while confirming the validity of the previously developed measures. The new index satisfies all criteria that can be applied to measures of bipartisanship, both theoretically and from the perspective of research practice. Therefore, it can serve as a useful addition to the toolkit of political research. Importantly, the data completeness requirements of the new measurement method are absolutely minimal. This allows its use for the analysis of historical electoral statistics, where all available election results are reduced to the shares of votes or seats obtained by the two largest parties.

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The authors declare that there are no conflicts of interest present.