In this paper we aim to understand the connectivity and communication characteristics of Twitter users who post content subsequently classified by human annotators as containing possible suicidal intent or thinking, commonly referred to as suicidal ideation. We achieve this understanding by analysing the characteristics of their social networks. Starting from a set of human annotated Tweets we retrieved the authors' followers and friends lists, and identified users who retweeted the suicidal content. We subsequently built the social network graphs. Our results show a high degree of reciprocal connectivity between the authors of suicidal content when compared to other studies of Twitter users, suggesting a tightly-coupled virtual community. In addition, an analysis of the retweet graph has identified bridge nodes and hub nodes connecting users posting suicidal ideation with users who were not, thus suggesting a potential for information cascade and risk of a possible contagion effect. This is particularly emphasised by considering the combined graph merging friendship and retweeting links.

中文翻译：

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分析 Twitter 上有自杀倾向的用户的连接和交流。


在本文中，我们旨在了解 Twitter 用户的连接性和沟通特征，这些用户发布的内容随后被人类注释者分类为包含可能的自杀意图或想法，通常称为自杀意念。我们通过分析他们的社交网络的特征来实现这一理解。从一组人工注释的推文开始，我们检索了作者的关注者和朋友列表，并识别了转发自杀内容的用户。我们随后构建了社交网络图。我们的结果显示，与其他针对 Twitter 用户的研究相比，自杀内容的作者之间存在高度的相互联系，这表明存在紧密耦合的虚拟社区。此外，对转发图的分析发现了将发布自杀意念的用户与没有自杀意念的用户连接起来的桥梁节点和枢纽节点，从而表明了信息级联的潜力和可能的传染效应的风险。通过考虑合并友谊和转发链接的组合图来特别强调这一点。