ABSTRACT Although computational approaches to ideology-based audience fragmentation are promising, they are not without limitations. First, most existing studies have focused on the US, and the cross-national validity of their results has rarely been tested. Second, previous studies that rely solely on behavioral data from social media tend to make strong analytical assumptions such as that Twitter users prefer to follow media and politicians whose ideological positions are similar to their own, and that the ideologies of political elites can be extrapolated to infer the ideologies of ordinary users. We aim to address these limitations. First, we focus on Japan to test the generalizability of US findings in an Asian context. Second, we do not rely solely on behavioral measurement but combine survey and social media data to infer the ideologies of Twitter users. Results indicate that our classifier built based on these self-reported ideologies produces more valid estimates than naïve extrapolation from views of the elites. Based on these improved estimates of Twitter users’ ideologies, we demonstrate that the ideological distributions of those who follow major Japanese media accounts on Twitter largely overlap, suggesting an absence of ideology-based audience fragmentation.

中文翻译：

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日本 Twittersphere 的新闻受众碎片化

摘要 尽管基于意识形态的受众碎片化的计算方法是有前途的，但它们并非没有限制。首先，大多数现有研究都集中在美国，其结果的跨国有效性很少得到检验。其次，之前仅依赖社交媒体行为数据的研究倾向于做出强有力的分析假设，例如 Twitter 用户更喜欢关注意识形态立场与自己相似的媒体和政客，政治精英的意识形态可以推断为推断普通用户的意识形态。我们旨在解决这些限制。首先，我们关注日本，以测试美国调查结果在亚洲背景下的普遍性。第二，我们不仅仅依靠行为测量，而是结合调查和社交媒体数据来推断 Twitter 用户的意识形态。结果表明，我们基于这些自我报告的意识形态构建的分类器比从精英的观点进行天真的推断产生了更有效的估计。基于对 Twitter 用户意识形态的这些改进估计，我们证明在 Twitter 上关注日本主要媒体账户的人的意识形态分布在很大程度上重叠，这表明没有基于意识形态的受众分裂。