iss. 2026 build 2026-05-10 vis. 52,847
colinhenry
researcher · political behavior × digital platforms
§ status
Postdoctoral researcher at the University of Zürich, Department of Political Science.
I'm part of the Political Behavior and Digital Media research group and lead on the SNSF Improving Public Discourse project. I study how digital platform architecture influences political behavior and community dynamics — with a focus on extremism and hate speech. Previously a research fellow at George Washington University's Dynamic Online Networks Lab.
§ papers
[ r & r ]
When Do Social Media Platforms Intervene in Online Hate Communities?
[ under review ]
Content and Competition: Structural Sources of Online Extremism
Job market paper
From Seeds to Communities: Adaptive Snowball Sampling and Community Detection in Cross-Platform Political Networks
[ working paper ]
Voting with Your Feeds: Platform Competition, Extremism, and the Limits of Tiebout Sorting
Related — Ideological fragmentation of the social media ecosystem (PNAS Nexus)
[ draft ]
Scrolling through Hate: TikTok, Hate Speech and Content Moderation
Indirect Effects of Content Moderation Errors: A Chatroom Experiment with AI Agents
Varieties of Platform Governance
§ projects
[ active ] SNSF Improving Public Discourse
role Technical lead
Improving Public Discourse — Swiss National Science Foundation grant hosted at the University of Zürich Digital Democracy Lab (PI: Fabrizio Gilardi). I design and maintain the data collection and classification infrastructure across the program's studies.
current Audit study of TikTok content moderation. Research assistants systematically review and flag content violating community guidelines; the platform's enforcement response is recorded and analyzed. Study launched March 2026 and is actively running.
methods audit methodology, two-stage NLP classification (multilingual BERT + custom 9B-parameter LLM), Postgres + Redis, Ansible, Flask
w/ Karsten Donnay (PI), Fabrizio Gilardi (PI), UZH DigDem Lab
[ active ] VIRENA
Indirect Effects of Content Moderation Errors: A Chatroom Experiment with AI Agents. VIRENA is an experimental platform simulating WhatsApp-style social media chatrooms. Prolific participants interact in real-time with LLM-powered bot personas under randomized moderation conditions — over-moderation, under-moderation, and regular moderation. The experiment tests how moderation errors shape conversation dynamics and perceptions of online spaces.
current 800-participant study live. Platform rebuild (VIRENA) underway for future experiments.
methods Svelte.js (frontend), PocketBase + Go (backend), Ollama / OpenAI (bot personas), Prolific (participant recruitment)
w/ Karsten Donnay, Giuliano Formisano, Emma Hoes, Jonathan Klues, Adiba Mahbub Proma, Fabrizio Gilardi (PI)
[ active ] Platform ABM
Voting with Your Feeds: Platform Competition, Extremism, and the Limits of Tiebout Sorting. Online platforms function as a system, not independent sites. Applying Tiebout's "voting with your feet" model to digital platforms, the paper shows that extremist communities act as utility vampires — degrading mainstream experiences and forcing displacement, raiding cycles, and ideological enclaves. The diversification premium grows with extremist threat intensity; governance type determines who benefits.
current Working paper — manuscript drafted, sensitivity analysis complete, figures integrated. Preparing for submission.
methods agent-based model, three-way ANOVA, bootstrap CIs, sensitivity analysis (OAT + Sobol indices). Python simulation; R/Python visualization
related — ideological fragmentation of the social media ecosystem (PNAS Nexus) →
[ wrapped ] Dissertation
"Governance, Competition, & Extremism: How the Structure of Social Media Platforms Radicalizes Communities." Platform governance structures create competitive dynamics between communities that systematically drive radicalization. A comparative study of digital architectures and how they shape collective behavior.
methods multi-platform analysis (Reddit, Twitter, Telegram, TikTok, YouTube), transformer models, network analysis, digital ethnography
w/ Jennifer Larson (co-chair), Cassy Dorff (co-chair), Emily Ritter, Anita Gohdes (Hertie School)
§ elsewhere
- Google Scholar — publications & citations
- University of Zürich — current affiliation
- Vanderbilt — job-market profile
- LinkedIn — professional network
- Bluesky — @henryhenryhenry.com
- Mastodon — @cmhenry_@mas.to
§ contact
researchers, search committees, curious visitors — say hi.