Though prior studies have analyzed the textual characteristics of online comments about politics, less is known about how selection into commenting behavior and exposure to other people’s comments changes the tone and content of political discourse. This article makes three contributions. First, we show that frequent commenters on Facebook are more likely to be interested in politics, to have more polarized opinions, and to use toxic language in comments in an elicitation task. Second, we find that people who comment on articles in the real world use more toxic language on average than the public as a whole; levels of toxicity in comments scraped from media outlet Facebook pages greatly exceed what is observed in comments we elicit on the same articles from a nationally representative sample. Finally, we demonstrate experimentally that exposure to toxic language in comments increases the toxicity of subsequent comments.

中文翻译：

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社交媒体的扭曲棱镜：自我选择和不文明行为如何助长在线评论毒性

尽管先前的研究已经分析了网络政治评论的文本特征，但对于评论行为的选择和对他人评论的曝光如何改变政治话语的基调和内容知之甚少。本文做出了三个贡献。首先，我们表明 Facebook 上的频繁评论者更有可能对政治感兴趣，有更多两极分化的意见，并在启发任务的评论中使用有毒语言。其次，我们发现在现实世界中评论文章的人平均使用的有毒语言比整个公众都多；从媒体出口 Facebook 页面上抓取的评论中的毒性水平大大超过了我们从具有全国代表性的样本中对相同文章得出的评论中观察到的水平。最后，