In recent years, social media has become an important platform for political discourse, being a site of both political conversations between voters and political advertisements from campaigns. While their individual influences on public discourse have been well-documented, the interplay between individual-level cognitive biases, social influence processes, dueling campaign efforts, and social media platforms remains unexamined. We introduce an agent-based model that integrates these dynamics and illustrates how their combination can lead to the formation of echo-chambers. We find that the range of political viewpoints that individuals are willing to consider is a key determinant in the formation of polarized networks and the emergence of echo-chambers, and show that aggressive political campaigns can have counter-productive outcomes by radicalizing supporters and alienating moderates. Our model results demonstrate how certain elements of public discourse and political polarization can be understood as the result of an interactive process of shifting individual opinions, evolving social networks, and political campaigns. We also introduce a dynamic empirical case, retweet-networks from the final stage of the 2016 U.S. Presidential Election, to show how our proposed model can be calibrated with real-world behavior.

中文翻译：

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社会认知偏见驱动的公共话语和社交网络回声室

近年来，社交媒体已成为政治对话的重要平台，既是选民之间的政治对话又是竞选活动的政治广告的网站。尽管他们对公共话语的个人影响已得到充分证明，但个人层面的认知偏见，社会影响过程，决斗运动和社交媒体平台之间的相互作用仍然没有得到检验。我们介绍了一个基于代理的模型，该模型集成了这些动态特性，并说明了它们的组合如何导致回声腔的形成。我们发现，个人愿意考虑的政治观点的范围是极化网络形成和回声腔的出现的关键决定因素，并表明激进的政治运动可以通过激化支持者和疏远温和派而产生适得其反的结果。我们的模型结果表明，公众意见和政治两极分化的某些要素是如何转变为个人意见，社交网络和政治运动互动过程的结果。我们还介绍了一个动态的经验案例，即从2016年美国总统大选的最后阶段转推网络，以展示我们提出的模型如何通过实际行为进行校准。