Author: searri

Intelligent Computing

Online hate speech can precipitate and also follow real-world violence, such as the U.S. Capitol attack on January 6, 2021. However, the current volume of content and the wide variety of extremist narratives raise major challenges for social media companies in terms of tracking and mitigating the activity of hate groups and broader extremist movements. This is further complicated by the fact that hate groups and extremists can leverage multiple platforms in tandem in order to adapt and circumvent content moderation within any given platform (e.g. Facebook). We show how the computational approach of dynamic Latent Dirichlet Allocation (LDA) may be applied to analyze similarities and differences between online content that is shared across social media platforms by extremist communities, including Facebook, Gab, Telegram, and VK between January and April 2021. We also discuss characteristics revealed by unsupervised machine learning about how hate groups leverage sites to organize, recruit, and coordinate within and across such online platforms.

Richard Sear, Nicholas Johnson Restrepo, Yonatan Lupu, Neil F. Johnson

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Exploring Hate (Brookings)

Rhys Leahy, Nicolas Velásquez, Nicholas Johnson Restrepo, Yonatan Lupu, Beth Goldberg, Neil F. Johnson

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Frontiers in Political Science

The current military conflict between Russia and Ukraine is accompanied by disinformation and propaganda within the digital ecosystem of social media platforms and online news sources. One month prior to the conflict’s February 2022 start, a Special Report by the U.S. Department of State had already highlighted concern about the extent to which Kremlin-funded media were feeding the online disinformation and propaganda ecosystem. Here we address a closely related issue: how Russian information sources feed into online extremist communities. Specifically, we present a preliminary study of how the sector of the online ecosystem involving extremist communities interconnects within and across social media platforms, and how it connects into such official information sources. Our focus here is on Russian domains, European Nationalists, and American White Supremacists. Though necessarily very limited in scope, our study goes beyond many existing works that focus on Twitter, by instead considering platforms such as VKontakte, Telegram, and Gab. Our findings can help shed light on the scope and impact of state-sponsored foreign influence operations. Our study also highlights the need to develop a detailed map of the full multi-platform ecosystem in order to better inform discussions aimed at countering violent extremism.

Rhys Leahy, Nicholas Johnson Restrepo, Richard Sear, Neil F. Johnson

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Advances in Artificial Intelligence and Machine Learning

The natural, physical and social worlds abound with feedback processes that make the challenge of modeling the underlying system an extremely complex one. This paper proposes an end-to-end deep learning approach to modelling such so-called complex systems which addresses two problems: (1) scientific model discovery when we have only incomplete/partial knowledge of system dynamics; (2) integration of graph-structured data into scientific machine learning (SciML) using graph neural networks. It is well known that deep learning (DL) has had remarkable success in leveraging large amounts of unstructured data into downstream tasks such as clustering, classification, and regression. Recently, the development of graph neural networks has extended DL techniques to graph structured data of complex systems. However, DL methods still appear largely disjointed with established scientific knowledge, and the contribution to basic science is not always apparent. This disconnect has spurred the development of physics-informed deep learning, and more generally, the emerging discipline of SciML. Modelling complex systems in the physical, biological, and social sciences within the SciML framework requires further considerations. We argue the need to consider heterogeneous, graph-structured data as well as the effective scale at which we can observe system dynamics. Our proposal would open up a joint approach to the previously distinct fields of graph representation learning and SciML.

Nicholas Gabriel, Neil F. Johnson

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Proceedings of the 2021 Conference of The Computational Social Science Society of the Americas

The COVID-19 pandemic sparked an online “infodemic” of potentially dangerous misinformation. We use machine learning to quantify COVID-19 content from opponents of establishment health guidance, in particular vaccination. We quantify this content in two different ways: number of topics and evolution of keywords. We find that, even in the early stages of the pandemic, the anti-vaccination community had the infrastructure to more effectively garner support than their pro-vaccination counterparts by exhibiting a broader array of discussion topics. This provided an advantage in terms of attracting new users seeking COVID-19 guidance online. We also find that our machine learning framework can pick up on the adaptive nature of discussions within the anti-vaccination community, tracking distrust of authorities, opposition to lockdown orders, and an interest in early vaccine trials. Our approach is scalable and hence tackles the urgent problem facing social media platforms of having to analyze huge volumes of online health misinformation. With vaccine booster shots being approved and vaccination rates stagnating, such an automated approach is key in understanding how to combat the misinformation that slows the eradication of the pandemic.

Richard Sear, Rhys Leahy, Nicholas Johnson Restrepo, Yonatan Lupu, Neil Johnson

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