Recommender systems and the amplification of extremist content
Open accessAbstract
Recommendation algorithms potentially amplifying extremist content has become a policy concern in recent years. We conduct a novel empirical experiment on three platforms (YouTube, Reddit, and Gab) to test this phenomenon. We find that YouTube’s “Recommended for you” system does promote extreme content. We synthesise the findings into the policy debate and argue that co-regulation may provide some solutions.
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YouTube's recommendations amplify far-right content, fostering echo chambers.
“while YouTube's recommendations amplify far-right content, fostering echo chambers [60,86].”
From A systematic review of echo chamber research: comparative analysis of conceptualizations, operationalizations, and varying outcomes (2025) · cites this paper as [60]
The Policy discussion reports that YouTube recommended more extreme videos after accounts interacted predominantly with far-right content, supporting the amplification claim under that condition. The Filter bubbles section says evidence for echo chambers is limited; the study does not establish that its recommendations fostered them. (LLM, conf=0.87)
Experimental — accuracy not yet measuredYouTube amplifies extreme and fringe content through algorithmic recommendations, while Reddit and Gab do not exhibit the same patterns.
“They found that YouTube amplifies extreme and fringe content through algorithmic recommendations, while Reddit and Gab do not exhibit the same patterns.”
From A systematic review of echo chamber research: comparative analysis of conceptualizations, operationalizations, and varying outcomes (2025) · cites this paper as [60]
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Cites
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Should we worry about filter bubbles?
Zuiderveen Borgesius, F. J., Trilling, D., Möller, J., Bodó, B., de Vreese, C. H., & Helberger, N. (2016) · Internet Policy Review · doi:10.14763/2016.1.401 · Cited by 541 · see citing works
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Wachter, S., & Mittelstadt, B. (2018) · doi:10.31228/osf.io/mu2kf · Cited by 463 · see citing works
Bruns, A. (2019) · Internet Policy Review · doi:10.14763/2019.4.1426 · Cited by 193 · cited 6× · see citing works
“There is little distinction made between the similar, yet different, concepts of filter bubbles and echo chambers (Zuiderveen Borgesius et al., 2016; Bruns, 2019).”
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- Authors
- Whittaker, J., Looney, S., Reed, A., & Votta, F.
- Affiliations
- Swansea University (GB)
- University of Amsterdam (NL)
- Corresponding author
- Whittaker, Joe
- Venue
- Internet Policy Review
- Published
- 2021-06-30
- Volume
- 10
- Issue
- 2
- ISSN
- 2197-6775 (ISSN-L)
- OpenAlex
- W3175993430
- Cited by
- 135
- References
- 4
- Citations by year
- 2026: 42 · 2025: 24 · 2024: 41 · 2023: 17 · 2022: 10 · 2021: 1
- FWCI
- 21.93
- Type
- journal article
- Language
- en
- Open access
- diamond
- doi.org
- Licence
- cc-by
- Locations
- Internet Policy Review (publishedVersion, cc-by)
- RePEc: Research Papers in Economics (submittedVersion)
- PEARL (University of Plymouth) (submittedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
- Econstor (Econstor) (submittedVersion, cc-by)
- Topics
- Social Sciences › Sociology and Political Science › Misinformation and Its Impacts
- Social Sciences › Safety Research › Ethics and Social Impacts of AI
- Social Sciences › Communication › Social Media and Politics
- Keywords
- recommender systems, algorithmic amplification, extremist content, YouTube, Reddit, Gab, content moderation, co-regulation, platform policies, online extremism
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