Echo chambers in online social networks, in which users prefer to interact only with ideologically-aligned peers, are believed to facilitate misinformation spreading and contribute to radicalize political discourse. In this paper, we gauge the effects of echo chambers in information spreading phenomena over political communication networks. Mining 12 million Twitter messages, we reconstruct a network in which users interchange opinions related to the impeachment of the former Brazilian President Dilma Rousseff. We define a continuous political leaning parameter, independent of the network’s structure, that allows to quantify the presence of echo chambers in the strongly connected component of the network. These are reflected in two well-separated communities of similar sizes with opposite views of the impeachment process. By means of simple spreading models, we show that the capability of users in propagating the content they produce, measured by the associated spreading capacity, strongly depends on their attitude. Users expressing pro-impeachment leanings are capable to transmit information, on average, to a larger audience than users expressing anti-impeachment leanings. Furthermore, the users’ spreading capacity is correlated to the diversity, in terms of political position, of the audience reached. Our method can be exploited to identify the presence of echo chambers and their effects across different contexts and shed light upon the mechanisms allowing to break echo chambers.

中文翻译：

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量化通过政治传播网络传播的信息中的回声腔效应

人们认为，在线社交网络中的回声室（echo chamber）中的用户只喜欢与意识形态上一致的同伴互动，这有助于错误信息的传播并促进激进的政治话语。在本文中，我们评估了回声室在政治传播网络上信息传播现象中的作用。通过挖掘1200万条Twitter消息，我们重建了一个网络，用户可以在该网络中交换与弹Brazilian巴西前总统迪尔玛·罗塞夫（Dilma Rousseff）有关的观点。我们定义了一个连续的政治倾向参数，与网络的结构无关，它可以量化网络的强连通组件中回声腔的存在。这些反映在两个大小相仿的社区中，对弹process程序的看法相反。通过简单的传播模型，我们表明，用户传播其产生的内容的能力（通过相关的传播能力来衡量）在很大程度上取决于他们的态度。与表示反对弹s倾向的用户相比，表达支持弹imp倾向的用户平均能够将信息传递给更大的受众。此外，就政治立场而言，用户的传播能力与所达到受众的多样性有关。可以利用我们的方法来确定回声腔的存在及其在不同环境中的影响，并阐明允许破坏回声腔的机制。与表示反对弹each倾向的用户相比，表达支持弹imp倾向的用户平均能够将信息传递给更大的受众。此外，就政治立场而言，用户的传播能力与所达到受众的多样性有关。可以利用我们的方法来确定回声腔的存在及其在不同环境中的影响，并阐明允许破坏回声腔的机制。与表示反对弹s倾向的用户相比，表达支持弹imp倾向的用户平均能够将信息传递给更大的受众。此外，就政治立场而言，用户的传播能力与所达到受众的多样性有关。可以利用我们的方法来确定回声腔的存在及其在不同环境中的影响，并阐明允许破坏回声腔的机制。