Social media creates the possibility for rapid, viral spread of content, but how many posts actually reach millions? And is misinformation special in how it propagates? We answer these questions by analyzing the virality of and exposure to information on Facebook during the U.S. 2020 presidential election. We examine the diffusion trees of the approximately 1 B posts that were re-shared at least once by U.S.-based adults from July 1, 2020, to February 1, 2021. We differentiate misinformation from non-misinformation posts to show that (1) misinformation diffused more slowly, relying on a small number of active users that spread misinformation via long chains of peer-to-peer diffusion that reached millions; non-misinformation spread primarily through one-to-many affordances (mainly, Pages); (2) the relative importance of peer-to-peer spread for misinformation was likely due to an enforcement gap in content moderation policies designed to target mostly Pages and Groups; and (3) periods of aggressive content moderation proximate to the election coincide with dramatic drops in the spread and reach of misinformation and (to a lesser extent) political content.

中文翻译：

---

2020 年美国大选期间 Facebook 上（错误）信息的传播和覆盖


社交媒体为内容的快速、病毒式传播创造了可能性，但有多少帖子真正覆盖了数百万人？错误信息的传播方式是否特殊？我们通过分析美国 2020 年总统大选期间 Facebook 上的病毒式传播和信息曝光率来回答这些问题。我们检查了从 2020 年 7 月 1 日至 2021 年 2 月 1 日美国成年人至少转发一次的大约 1 个 B 帖子的扩散树。我们将错误信息与非错误信息帖子区分开来，以表明 （1） 错误信息的传播速度较慢，依赖于少数活跃用户通过覆盖数百万的长长的点对点传播链传播错误信息;非错误信息主要通过一对多功能（主要是页面）传播;（2） 点对点传播对错误信息的相对重要性可能是由于主要针对页面和群组的内容审核政策的执行差距;（3） 接近选举的激进内容审核时期与错误信息和（在较小程度上）政治内容的传播和覆盖面急剧下降相吻合。