Misinformation proliferation on social media platforms is a pervasive threat to the integrity of online public discourse. Genuine users, susceptible to others' influence, often unknowingly engage with, endorse, and re-share questionable pieces of information, collectively amplifying the spread of misinformation. In this study, we introduce an empirical framework to investigate users' susceptibility to influence when exposed to unreliable and reliable information sources. Leveraging two datasets on political and public health discussions on Twitter, we analyze the impact of exposure on the adoption of information sources, examining how the reliability of the source modulates this relationship. Our findings provide evidence that increased exposure augments the likelihood of adoption. Users tend to adopt low-credibility sources with fewer exposures than high-credibility sources, a trend that persists even among non-partisan users. Furthermore, the number of exposures needed for adoption varies based on the source credibility, with extreme ends of the spectrum (very high or low credibility) requiring fewer exposures for adoption. Additionally, we reveal that the adoption of information sources often mirrors users' prior exposure to sources with comparable credibility levels. Our research offers critical insights for mitigating the endorsement of misinformation by vulnerable users, offering a framework to study the dynamics of content exposure and adoption on social media platforms.

翻译：社交媒体平台上错误信息的泛滥对在线公共讨论的完整性构成了普遍威胁。易受他人影响的真实用户往往在不知情的情况下参与、认可并转发可疑信息，从而集体放大错误信息的传播。在本研究中，我们引入了一个经验框架，以考察用户暴露于不可靠与可靠信息源时对影响的易感性。利用推特上关于政治和公共卫生讨论的两个数据集，我们分析了信息接触对采纳信息源的影响，并探讨了信息源可靠性如何调节这一关系。研究结果表明，增加接触会提升采纳的可能性。用户倾向于在比高可信度信息源更少的接触次数下采纳低可信度信息源，这一趋势甚至在无党派用户中依然存在。此外，采纳所需的接触次数因信息源可信度而异：极端可信度（极高或极低）的信息源所需的接触次数更少。我们还发现，信息源的采纳往往反映了用户先前对类似可信度水平信息源的接触。本研究为缓解弱势用户对错误信息的认可提供了关键见解，并构建了一个框架来研究社交媒体平台上内容接触与采纳的动态机制。