Do the policy preferences expressed through political participation represent the citizens as a whole? Previous studies argue that there is no ideological bias in voting participation in Japan. However, previous studies have only analyzed Japan up to 2010, and it is unclear whether ideological bias was consistently absent in voting participation in the 2010s. In the 2010s, ideological issues, such as the maintenance of nuclear power plants or the acceptance of collective self-defense, emerged in Japan, and the two major political parties, the Liberal Democratic Party and Democratic Party of Japan, became increasingly polarized. Considering these changes, the influence of ideology on political participation may be growing. Therefore, this paper examines the relationship between people’s ideological positions and political participation using voter surveys conducted between 2001 and 2017. I find that since 2012, the more ideologically extreme Japanese voters are, the more they participate in voting. Furthermore, the same is true for other forms of participation. In general, the voices of ideologically moderate Japanese are becoming less represented by political parties and politicians.

中文翻译：

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日本的意识形态极端主义与政治参与

通过政治参与表达的政策偏好是否代表了整个公民？先前的研究认为，日本的投票参与不存在意识形态偏见。然而，之前的研究只分析了截至 2010 年的日本，尚不清楚 2010 年代投票参与是否始终不存在意识形态偏见。2010年代，日本出现了维护核电站或接受集体自卫等意识形态问题，日本两大政党自民党和民主党日益两极分化。考虑到这些变化，意识形态对政治参与的影响可能会越来越大。所以，本文通过 2001 年至 2017 年间进行的选民调查，研究了人们的意识形态立场与政治参与之间的关系。我发现，自 2012 年以来，意识形态越极端的日本选民参与投票的次数越多。此外，其他形式的参与也是如此。总体而言，意识形态温和的日本人的声音在政党和政治家中的代表越来越少。