Martel Cameron, Mosleh Mohsen, Yang Qi, Zaman Tauhid, Rand David G
Sloan School of Management, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
Management Department, University of Exeter Business School, Exeter EX4 4PU, UK.
PNAS Nexus. 2024 Apr 15;3(5):pgae161. doi: 10.1093/pnasnexus/pgae161. eCollection 2024 May.
There is strong political assortment of Americans on social media networks. This is typically attributed to preferential tie formation (i.e. homophily) among those with shared partisanship. Here, we demonstrate an additional factor beyond homophily driving assorted networks: preferential of social ties. In two field experiments on Twitter, we created human-looking bot accounts that identified as Democrats or Republicans, and then randomly assigned users to be followed by one of these accounts. In addition to preferentially following-back copartisans, we found that users were 12 times more likely to block counter-partisan accounts compared to copartisan accounts in the first experiment, and 4 times more likely to block counter-partisan accounts relative to a neutral account or a copartisan account in the second experiment. We then replicated these findings in a survey experiment and found evidence of a key motivation for blocking: wanting to avoid seeing any content posted by the blocked user. Additionally, we found that Democrats preferentially blocked counter-partisans more than Republicans, and that this asymmetry was likely due to blocking accounts who post low-quality or politically slanted content (rather than an asymmetry in identity-based blocking). Our results demonstrate that preferential blocking of counter-partisans is an important phenomenon driving political assortment on social media.
美国人在社交媒体网络上存在强烈的政治分类现象。这通常归因于具有相同党派关系的人之间形成的偏好性联系（即同质性）。在此，我们证明了除同质性之外，还有一个驱动分类网络的额外因素：社交关系的偏好性。在推特上的两项实地实验中，我们创建了伪装成人类的机器人账户，这些账户分别标识为民主党人或共和党人，然后随机分配用户由其中一个账户进行关注。除了优先回关同党派人士外，我们发现，在第一个实验中，用户屏蔽对立党派账户的可能性是屏蔽同党派账户的12倍；在第二个实验中，相对于中立账户或同党派账户，用户屏蔽对立党派账户的可能性是其4倍。然后，我们在一项调查实验中重复了这些发现，并找到了屏蔽行为的一个关键动机的证据：想要避免看到被屏蔽用户发布的任何内容。此外，我们发现民主党人比共和党人更倾向于屏蔽对立党派人士，而且这种不对称可能是由于屏蔽那些发布低质量或政治倾向内容的账户（而不是基于身份的屏蔽方面的不对称）。我们的研究结果表明，对对立党派人士的偏好性屏蔽是推动社交媒体上政治分类的一个重要现象。
