This study documents historical trends of size and political diversity in Americans’ discussion networks, which are often seen as important barometers of social and political health. Contrasting findings from data drawn out of a nationally representative survey experiment of 1,055 Americans during the contentious 2016 U.S. presidential election to data arising from 11 national data sets covering nearly three decades, we find that Americans’ core networks are significantly smaller and more politically homogeneous than at any other period. Several methodological artifacts seem unlikely to account for the effect. We show that in this period, more than before, “important matters” were often framed as political matters, and that this association probably accounts for the smaller networks.

中文翻译：

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美国的政治孤立

这项研究记录了美国人讨论网络中规模和政治多样性的历史趋势，这些网络通常被视为社会和政治健康的重要晴雨表。将在有争议的 2016 年美国总统大选期间对 1,055 名美国人进行的全国代表性调查实验得出的数据与来自近 30 年的 11 个国家数据集的数据进行对比，我们发现美国人的核心网络明显更小，在政治上更同质化。在任何其他时期。一些方法论上的人工制品似乎不太可能解释这种影响。我们表明，在这一时期，比以往更多的是，“重要事项”经常被视为政治事项，并且这种关联可能解释了较小的网络。