Social media, the modern public square, is vulnerable to manipulation. By controlling inauthentic accounts impersonating humans, malicious actors can amplify disinformation within target communities. The consequences of such operations are difficult to evaluate due to the ethical challenges posed by experiments that would influence online communities. Here we use a social media model that simulates information diffusion in an empirical network to quantify the impacts of adversarial manipulation tactics on the quality of content. We find that social media features such as high information load, limited attention, and the presence of influentials exacerbate the vulnerabilities of online communities. Infiltrating a community is the most harmful tactic that bad actors can exploit and the most likely to make low-quality content go viral. The harm is further compounded by inauthentic agents flooding the network with engaging low-quality content, but is mitigated when influential or vulnerable individuals are targeted. These insights suggest countermeasures that platforms could employ to increase the resilience of social media users to manipulation.

翻译：社交媒体作为现代公共空间，易受操纵。通过控制冒充人类的虚假账户，恶意行为者可在目标社区内放大虚假信息。由于实验会影响在线社区所引发的伦理挑战，此类操作的影响难以评估。本文采用基于实证网络模拟信息扩散的社交媒体模型，量化对抗性操纵策略对内容质量的影响。研究发现，信息负载高、注意力有限及存在影响力用户等社交媒体特征加剧了在线社区的脆弱性。渗透社区是恶意行为者可利用的最具危害性策略，也是最可能使低质量内容病毒式传播的手段。虚假账户以吸引人的低质量内容淹没网络会进一步加剧危害，但当针对影响力用户或脆弱个体时，危害程度反而减弱。这些见解为平台提升社交媒体用户抵御操纵的韧性提供了对策参考。