Cited by 60Social Media and PoliticsMisinformation and Its ImpactsMedia Influence and Politics

A systematic review of echo chamber research: comparative analysis of conceptualizations, operationalizations, and varying outcomes

Open access
Hartmann, David, Wang, Sonja Mei, Pohlmann, Lena, Berendt, Bettina·2025·Journal of Computational Social Science

Abstract

This systematic review synthesizes research on echo chambers and filter bubbles to explore the reasons behind dissent regarding their existence, antecedents, and effects. It provides a taxonomy of conceptualizations and operationalizations, analyzing how measurement approaches and contextual factors influence outcomes. The review of 129 studies identifies variations in measurement approaches, as well as regional, political, cultural, and platform-specific biases, as key factors contributing to the lack of consensus. Studies based on homophily and computational social science methods often support the echo chamber hypothesis, while research on content exposure and broader media environments, such as surveys, tends to challenge it. Group behavior, cultural influences, instant messaging platforms, and short video platforms remain underexplored. The strong geographic focus on the United States further highlights the need for studies in multi-party systems and regions beyond the Global North. Future research should prioritize cross-platform studies, continuous algorithmic audits, and investigations into the causal links between polarization, fragmentation, and echo chambers to advance the field. This review also provides recommendations for using the EU’s Digital Services Act to enhance research in this area and conduct studies outside the US in multi-party systems. By addressing these gaps, this review contributes to a more comprehensive understanding of echo chambers, their measurement, and their societal impacts.

AI snapshot

Written from the paper’s full text.

TL;DR

This systematic review of 129 studies finds that echo chamber research diverges largely because studies conceptualize and operationalize echo chambers differently: homophily/CSS studies often support the echo chamber hypothesis, while content-exposure/survey studies often challenge it. It identifies regional, political, cultural, and platform-specific biases, especially a US focus and understudied platforms, as key reasons for the lack of consensus.

Key findings

  • Across 129 studies published 2014–2023, 76 found attitude-based homophily supporting the echo chamber hypothesis, 27 reported mixed results, and 26 provided little to no support.
  • Method and conceptualization align with outcomes: 85 studies used data-driven computational social science methods and often supported echo chambers, while 20 surveys and 10 experiments more often produced mixed or negative findings, especially when examining broader media diets.
  • Geographic and platform biases are substantial: 54 studies were conducted in the US; among the top 10 most popular platforms, only Facebook and YouTube were addressed, while Instagram, WhatsApp, Telegram, TikTok, and WeChat were notably absent; only 7 CSS studies compared platforms.
  • Effects linked to echo chambers include polarization (nearly a third of studies), misinformation (23 studies, 7 explicitly focused), and extremism (14 studies), but causal direction remains unclear.

Methods

  • PRISMA 2020 systematic review searching Web of Science, Scopus, ACM, IEEE, Google Scholar, and DBLP; from 1,706 results and 514 duplicates removed, 1,051 unique publications were screened, yielding 129 peer-reviewed studies.
  • Inclusion required quantitative designs (observational data, surveys, mixed methods, experiments) on the existence, antecedents, effects, or other properties of echo chambers on social media; English-language only; screening used a hierarchical cascade with Cohen’s κ = 0.62 for title/abstract and κ = 0.66 for full-text coding.
  • Analysis used inductive content analysis in MAXQDA and narrative synthesis with bibliometric features; meta-analysis was not possible because research designs were too dissimilar.

Limitations

  • The paper states publication bias, location/accessibility bias (11 studies inaccessible), language bias (English-only), and outcome reporting bias; it also states initial inter-coder agreement was moderate and final Cohen’s κ = 0.66, leaving room for improvement.
  • The paper states that no meta-analysis was possible due to dissimilar research designs, so findings rely on narrative synthesis.
  • Evident from the text: the corpus is restricted to peer-reviewed English quantitative social media studies, excluding qualitative, non-English, and non-social-media work; the US-heavy sample and platform API access bias further limit generalizability.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1007/s42001-025-00381-z

Cites

179 of 180 references verified1 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

91 of 163 cited sources checked · 28 supported · 3 flagged · accuracy not yet measured

  • Findingreasoning

    Most research fails to adequately address dynamic shifts in algorithmic filtering.

    “Although a few studies have conducted continuous audits to examine how algorithms evolve (e.g., [147,166]), most research fails to address these dynamic shifts adequately.”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [147] Srba, I., Moro, R., Tomlein, M., Pecher, B., Simko, J., Stefancova, E., Kompan, M., Hrckova, A., Podrouzek, J., Gavornik, A., & Bielikova, M. (2023). Auditing youtube’s recommendation algorithm for misinformation filter bubbles. ACM Transactions on Recommender Systems 1(1). source

      The citation is attached to the sentence’s example of a study conducting continuous audits to examine how algorithms evolve. This paper says instead that it ran its experiments in the shortest possible time frame to minimize the risk of algorithm changes (Methods, p. 12), and describes continuous auditing as future work (Discussion, p. 30). It does identify YouTube’s ongoing development as an underinvestigated issue (Related Work, p. 8), but it is not an example of a continuous audit. (LLM, conf=0.88)

      Checked by a reasoning model — may be wrong.

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    • cites [166] Tomlein, M., Pecher, B., Simko, J., Srba, I., Moro, R., Stefancova, E., Kompan, M., Hrckova, A., Podrouzek, J., & Bielikova, M. (2021). An audit of misinformation filter bubbles on youtube: Bubble bursting and recent behavior changes. In Fifteenth ACM conference on recommender systems (pp. 1–11). Association for Computing Machinery, New York, NY, USA. https://doi.org/10.1145/3460231.3474241 source

      The Related Work section (p. 4) says prior YouTube misinformation-filter-bubble studies had not investigated how YouTube’s adaptive systems develop and improve. The Study Design section (p. 5) compares a March 2021 audit with a mid-2019 study, addressing change over time. This supports the point for that research area, but not the broader assertion that most research on algorithmic filtering inadequately addresses dynamic shifts. (LLM, conf=0.82)

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  • Findingcitation

    Cinelli et al. found that Facebook facilitates the formation of segregated communities with limited exposure to cross-cutting content, especially compared to Reddit.

    “For example, Cinelli et al. [17] found that Facebook facilitates the formation of segregated communities with limited exposure to cross-cutting content, especially compared to Reddit.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [17] Cinelli, M., Morales, G.D.F., Galeazzi, A., Quattrociocchi, W., & Starnini, M. (2021). The echo chamber effect on social media. Proceedings of the National Academy of Sciences of the United States of America 118(9). source
  • Findingcitation

    Polarization often arises during contentious events, such as elections, where users amplify content from ideologically aligned sources.

    “Polarization often arises during contentious events, such as elections, where users amplify content from ideologically aligned sources [55,56].”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [55] Masip, P., Suau, J., & Ruiz-Caballero, C. (2020). Incidental exposure to non-like-minded news through social media: Opposing voices in echo-chambers’ news feeds. Media and Communication, 8(4), 53–62. source

      Section 2, “Selective Exposure and the New Media Environment” (page unavailable), says that distribution of content shared by politically like-minded contacts can reinforce polarization. It does not establish that polarization often arises during contentious events such as elections, or that users specifically amplify content from ideologically aligned sources. (LLM, conf=0.84)

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    • cites [56] Guarino, S., Trino, N., Celestini, A., Chessa, A., & Riotta, G. (2020). Characterizing networks of propaganda on twitter: a case study. Applied Network Science 5(1). source

      The Polarized retweet graphs section reports strongly polarized users in the referendum discussion, and the Clustering structure section finds politically aligned clusters in retweet networks. This supports the claim’s election-like example, but the paper does not establish that polarization often arises during contentious events or that amplifying content from ideologically aligned sources causes it. (LLM, conf=0.83)

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  • Findingown data

    Most studies examined specific groups or communities on platforms, such as climate change deniers, vaccination opponents and advocates, and Trump supporters.

    “Most studies examined specific groups or communities on platforms, such as climate change deniers (e.g., [94]), vaccination opponents and advocates (e.g., [49]), and Trump supporters (e.g., [16]).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [94] Cann, T. J. B., Weaver, I. S., & Williams, H. T. P. (2021). Ideological biases in social sharing of online information about climate change. PLOS ONE 16(4). source
    • cites [49] Schmidt, A. L., Zollo, F., Scala, A., Betsch, C., & Quattrociocchi, W. (2018). Polarization of the vaccination debate on facebook. Vaccine, 36(25), 3606–3612. https://doi.org/10.1016/j.vaccine.2018.05.040 source
    • cites [16] Boulianne, S., Koc-Michalska, K., & Bimber, B. (2020). Right-wing populism, social media and echo chambers in western democracies. New Media & Society, 22(4), 683–699. https://doi.org/10.1177/1461444819893983 source
  • Premisecitation

    Shared partisanship increases the likelihood of social tie formation on platforms like Twitter, reinforcing homophily.

    “Many studies demonstrated that shared partisanship increases the likelihood of social tie formation on platforms like Twitter, reinforcing homophily (e.g., [93][94][95]).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [93] Mosleh, M., Pennycook, G., Arechar, A. A., & Rand, D. G. (2021). Cognitive reflection correlates with behavior on twitter. Nature Communications 12(1). source

      The Discussion (page unavailable) says supporters of the same party are much more likely to interact with co-partisans, supporting the homophily point. But this paper studies cognitive reflection and Twitter behavior; it does not itself demonstrate that shared partisanship increases social tie formation. That more specific result appears as the title of a separate study in its References. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [94] Cann, T. J. B., Weaver, I. S., & Williams, H. T. P. (2021). Ideological biases in social sharing of online information about climate change. PLOS ONE 16(4). source

      The Introduction describes echo chambers in which users associate with people and sources that reinforce their beliefs, and the Discussion reports ideologically segregated Twitter information-sharing communities. But the study examines shared links, not whether shared partisanship increases the likelihood of forming user-to-user social ties. No page numbers are supplied in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [95] Guerrero-Sole, F. (2018). Interactive behavior in political discussions on twitter: Politicians, media, and citizens’ patterns of interaction in the 2015 and 2016 electoral campaigns in spain. Social Media + Society 4(4). https://doi.org/10.1177/2056305118808776 source
  • May combine two claims. 102
  • Classified as probably not a substantial claim. 105
  • The quote only partly states this claim. 1
  • May combine two claims.

    Findingcitation

    Bail et al. challenge the polarization assumption, showing that social media use can increase exposure to non-partisan content.

    “Supporting this, Bail et al. [2] further challenge the polarization assumption, showing that social media use can increase exposure to non-partisan content.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [2] Bail, C. A., Argyle, L. P., Brown, T. W., Bumpus, J. P., Chen, H., Hunzaker, M. B. F., Lee, J., Mann, M., Merhout, F., & Volfovsky, A. (2018). Exposure to opposing views on social media can increase political polarization. Proceedings of the National Academy of Sciences of the United States of America, 115(37), 9216–9221. source

      The Research Design section says the intervention exposed Twitter users to messages from political accounts with opposing ideologies, not non-partisan content. The Abstract reports that Republicans became substantially more conservative after following a liberal bot; the paper does not show that ordinary social media use increases exposure to non-partisan content. Page numbers are unavailable in our copy. (LLM, conf=0.89)

      Checked by a reasoning model — may be wrong.

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    The amount of media a person consumes is anti-proportional to their chance of being trapped in an echo chamber, which contradicts findings by CSS studies that engagement and echo chambers are positively correlated.

    “They find that the amount of media a person consumes is anti-proportional to their chance of being trapped in an echo chamber, which contradicts findings by CSS studies [48,50,66,67] that find that engagement and echo chambers are positively correlated.”
    Quote in the paperNot a substantial claim4 of 4 sources checked
    • cites [48] Del Vicario, M., Bessi, A., Zollo, F., Petroni, F., Scala, A., Caldarelli, G., Stanley, H. E., & Quattrociocchi, W. (2016). The spreading of misinformation online. Proceedings of the National Academy of Sciences of the United States of America, 113(3), 554–559. source

      The citation is attached to the claim that engagement and echo chambers are positively correlated, not to the preceding claim about an inverse relationship. Results and Discussion reports that sharing largely occurs within homogeneous clusters, supporting a qualitative link between engagement and echo chambers. It does not establish that people who consume more media are more likely to be in an echo chamber or report the stated correlation. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
    • cites [50] Zollo, F., Bessi, A., Del Vicario, M., Scala, A., Caldarelli, G., Shekhtman, L., Havlin, S., & Quattrociocchi, W. (2017). Debunking in a world of tribes. PLOS ONE 12(7). source

      The Results and discussion section (‘Echo chambers’; page unavailable) finds that Facebook users are highly polarized and mainly interact with one type of content, supporting a link between engagement and echo chambers. It does not show that greater amounts of engagement are correlated with a greater likelihood of being in an echo chamber. The inverse relationship is attributed to a different study in the citing sentence, not to this source. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [66] Schmidt, A. L., Peruzzi, A., Scala, A., Cinelli, M., Pomerantsev, P., Applebaum, A., Gaston, S., Fusi, N., Peterson, Z., Severgnini, G., Cesco, A. F., Casati, D., Novak, P. K., Stanley, H. E., Zollo, F., & Quattrociocchi, W. (2020). Measuring social response to different journalistic techniques on facebook. Humanities & Social Sciences Communications, 7(1), 17. source

      The Introduction says users continue selecting belief-consistent content as they enter echo chambers, supporting a qualitative link between content selection and echo-chamber behavior. The Results examine news framing and commenting, not whether greater engagement or media consumption is positively correlated with being in an echo chamber. The inverse relationship is attributed to a different study in the citing sentence, not to this source. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [67] Koivula, A., Kaakinen, M., Oksanen, A., & Rasanen, P. (2019). The role of political activity in the formation of online identity bubbles. Policy and Internet, 11(4), 396–417. source

      The Discussion (page not available in our copy) says frequent social media use has an effect on identity-bubble formation, and the Results report a positive association involving social media activity and identity-bubble reinforcement. The paper does not find that consuming more media lowers a person's chance of being in an echo chamber; it studies social media activity and online identity bubbles rather than media consumption generally. (LLM, conf=0.86)

      Checked by a reasoning model — may be wrong.

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  • May combine two claims.

    Premisecitation

    There is conflicting evidence on the existence and effects of echo chambers.

    “However, there is conflicting evidence on the existence and effects of echo chambers.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [15] Terren, L., & Borge, R. (2021). Echo chambers on social media: A systematic review of the literature. Review of Communication Research, 9, 99–118. https://doi.org/10.12840/ISSN.2255-4165.028 source

      The Highlights (p. 100) report studies finding clear evidence of social-media echo chambers and others finding none, supporting conflicting evidence about their existence. The Introduction (p. 100) describes competing views of their potential consequences, but the passages do not establish conflicting empirical evidence about their effects. (LLM, conf=0.84)

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    • cites [21] Arguedas, A. R., Robertson, C., Fletcher, R., & Nielsen, R. K. (2022). Echo chambers, filter bubbles, and polarisation: A literature review. Reuter Institute for the Study of Journalism. Accessed 10 March 2022.

      Not checked in the free run.

  • May combine two claims.

    Findingcitation

    Users often consume partisan content, reinforcing existing beliefs.

    “Users often consume partisan content, reinforcing existing beliefs [24,54].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [24] Kitchens, B., Johnson, S. L., & Gray, P. (2020). Understanding echo chambers and filter bubbles: The impact of social media on diversification and partisan shifts in news consumption. MIS Quarterly, 44(4), 1619–1649. source
    • cites [54] Nikolov, D., Lalmas, M., Flammini, A., & Menczer, F. (2019). Quantifying biases in online information exposure. Journal of the Association for Information Science and Technology, 70(3), 218–229. https://doi.org/10.1002/asi.24121 source

      The Background (p. 5) reports that online users are somewhat more likely to encounter news aligned with their worldviews, supporting the selective-exposure part of the claim. But the Discussion (p. 15) says this study did not analyze content or the political bias of news sources, and it does not establish that consuming such content reinforces users’ beliefs. (LLM, conf=0.86)

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  • May combine two claims.

    Findingcitation

    Attitude-based homophily is particularly pronounced in segregated networks, such as scientific vs. conspiracy communities, and among groups divided by political affiliation, such as Democrats and Republicans.

    “This phenomenon is particularly pronounced in segregated networks, such as”
    Quote in the paperNot a substantial claim4 of 4 sources checked
    • cites [47] Bessi, A., Zollo, F., Del Vicario, M., Puliga, M., Scala, A., Caldarelli, G., Uzzi, B., & Quattrociocchi, W. (2016). Users polarization on facebook and youtube. PLOS ONE 11(8). source

      The Results and Discussion section (“Polarized and Homogeneous Communities”; page unavailable) reports that users concentrated on either science or conspiracy content and formed well-separated echo chambers. The paper does not examine segregation by political affiliation or compare Democrats and Republicans, so it supports only the science-versus-conspiracy example. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [48] Del Vicario, M., Bessi, A., Zollo, F., Petroni, F., Scala, A., Caldarelli, G., Stanley, H. E., & Quattrociocchi, W. (2016). The spreading of misinformation online. Proceedings of the National Academy of Sciences of the United States of America, 113(3), 554–559. source

      The Results and Discussion section reports that sharing links are predominantly homogeneous and that science and conspiracy content circulate in distinct echo chambers. It does not report a comparison between Democrats and Republicans or establish the claim for groups divided by political affiliation. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [49] Schmidt, A. L., Zollo, F., Scala, A., Betsch, C., & Quattrociocchi, W. (2018). Polarization of the vaccination debate on facebook. Vaccine, 36(25), 3606–3612. https://doi.org/10.1016/j.vaccine.2018.05.040 source

      The Introduction (p. 2) describes users selecting belief-consistent information and forming polarized groups with opposing views that rarely interact. It does not establish that attitude-based homophily is particularly pronounced in such networks, or discuss scientific versus conspiracy communities or Democrats versus Republicans as the claimed examples. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [50] Zollo, F., Bessi, A., Del Vicario, M., Scala, A., Caldarelli, G., Shekhtman, L., Havlin, S., & Quattrociocchi, W. (2017). Debunking in a world of tribes. PLOS ONE 12(7). source

      The Conclusions (page not provided) describe highly segregated Facebook communities centered on scientific and conspiracy topics, and the Echo chambers section reports that users are polarized toward one or the other. The paper does not address homophily between Democrats and Republicans, so the political-affiliation example is not supported by this source. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Findingcitation

    Studies examining major political events, including the 2015 Polish elections, the impeachment of Brazilian President Dilma Rousseff, and the 2016 U.S. elections, support the echo chamber hypothesis, showing pronounced clustering in user interactions.

    “Studies examining major political events, including the 2015 Polish elections [51], the impeachment of Brazilian President Dilma Rousseff [52], and the 2016 U.S. elections [53], also support the echo chamber hypothesis, showing pronounced clustering in user interactions.”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites [51] Batorski, D., & Grzywinska, I. (2018). Three dimensions of the public sphere on facebook. Information, Communication & Society, 21(3), 356–374. https://doi.org/10.1080/1369118X.2017.1281329 source
    • cites [52] Cota, W., Ferreira, S. C., Pastor-Satorras, R., & Starnini, M. (2019). Quantifying echo chamber effects in information spreading over political communication networks. EPJ Data Science 8(1). source
    • cites [53] Guo, L., Rohde, J. A., & Wu, H. D. (2020). Who is responsible for twitter’s echo chamber problem? Evidence from 2016 us election networks. Information, Communication & Society, 23(2), 234–251. https://doi.org/10.1080/1369118X.2018.1499793 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    The review follows the PRISMA 2020 guideline.

    “We follow the PRISMA 2020 [26] guideline to present a transparent account of how we conducted our systematic review.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [26] Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D., Shamseer, L., Tetzlaff, J. M., Akl, E. A., Brennan, S. E., Chou, R., Glanville, J., Grimshaw, J. M., Hróbjartsson, A., Lalu, M. M., Li, T., Loder, E. W., Mayo-Wilson, E., McDonald, S., … Moher, D. (2021). The PRISMA 2020 statement: An updated guideline for reporting systematic reviews. Systematic Reviews, 18(3), 1003583. source
  • May combine two claims.

    Findingcitation

    Differences in datasets used across studies have led to inconsistent results, with much of the evidence relying on data collected in 2020.

    “Differences in datasets used across studies have led to inconsistent results, with much of the evidence relying on data collected in 2020.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [15] Terren, L., & Borge, R. (2021). Echo chambers on social media: A systematic review of the literature. Review of Communication Research, 9, 99–118. https://doi.org/10.12840/ISSN.2255-4165.028 source

      The Highlights (before p. 100) link differing findings to the type of data used: studies finding clear evidence of echo chambers used digital trace data, while those finding none used self-reported data. They describe the review as covering the state of the literature at January 2020, not as relying largely on data collected in 2020. The data-collection-year claim is unsupported. (LLM, conf=0.87)

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  • May combine two claims.

    Findingcitation

    Gao et al. analyzed platforms such as Douyin, TikTok, and Bilibili, demonstrating how feed algorithms foster selective exposure and homophily, contributing to echo chamber formation, while cultural differences can correlate with the development of echo chambers.

    “However, a study by Gao et al. [64] analyzed platforms such as Douyin, TikTok, and Bilibili, demonstrating how feed algorithms foster selective exposure and homophily, ultimately contributing to echo chamber formation, while also highlighting that cultural differences can correlate with the development of echo chambers and their influence is not equivalently likely for each community and culture.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [64] Gao, Y., Liu, F., & Gao, L. (2023). Echo chamber effects on short video platforms. Scientific Reports, 13, 6282. https://doi.org/10.1038/s41598-023-33370-1 source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Users of social media platforms can choose to be exposed to conversations with like-minded users and content that reflects their thinking, thus reinforcing their existing preferences or beliefs.

    “Users of social media platforms can choose to be exposed to conversations with like-minded users and content that reflects their thinking, thus reinforcing their existing preferences or beliefs [11,12].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [11] Van Aelst, P., Strömbäck, J., Aalberg, T., Esser, F., De Vreese, C., Matthes, J., Hopmann, D., Salgado, S., Hubé, N., & Stępińska, A. (2017). Political communication in a high-choice media environment: a challenge for democracy? Annals of the International Communication Association 41(1), 3–27. source
    • cites [12] Dubois, E., & Blank, G. (2018). The echo chamber is overstated: the moderating effect of political interest and diverse media. Information Communication & Society 21(5, SI), 729–745 https://doi.org/10.1080/1369118X.2018.1428656 source
  • May combine two claims.

    Premisecitation

    Offline political success correlates with detachment (isolation of political actors) in online networks, suggesting that online fragmentation is not solely a product of digital interactions but also reflects offline political dynamics.

    “Bright [89] found that offline political success correlates with detachment (isolation of political actors) in online networks, suggesting that online fragmentation is not solely a product of digital interactions but also reflects offline political dynamics.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [89] Bright, J. (2018). Explaining the emergence of political fragmentation on social media: The role of ideology and extremism. Journal of Computer-Mediated Communication, 23(1), 17–33. source
  • May combine two claims.

    Premisecitation

    Younger and less educated users are more susceptible to personalized content, potentially limiting exposure to diverse viewpoints.

    “Bodo et al. [82] highlighted that younger and less educated users are more susceptible to personalized content, potentially limiting exposure to diverse viewpoints.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [82] Bodo, B., Helberger, N., Eskens, S., & Moller, J. (2019). Interested in diversity: The role of user attitudes, algorithmic feedback loops, and policy in news personalization. Digital Jorunalism, 7(2), 206–229. https://doi.org/10.1080/21670811.2018.1521292 source
  • May combine two claims.

    Premisecitation

    Specific hub nodes play a pivotal role in spreading misinformation within networks and shaping echo chambers.

    “Specific hub nodes play a pivotal role in spreading misinformation within networks and shaping echo chambers [99].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [99] Asatani, K., Yamano, H., Sakaki, T., & Sakata, I. (2021). Dense and influential core promotion of daily viral information spread in political echo chambers. Scientific Reports 11(1). source

      The Results (pp. unavailable) show that top influencers spread large amounts of information within political echo chambers and suggest that their connected networks may contribute to opinion homogeneity. The paper does not establish that the information these hubs spread is misinformation; its Introduction distinguishes its study of daily information spread from earlier studies focused on fake news or rumours. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Findingcitation

    Nordbrandt and Nyhan et al. observed that while social media usage does not directly influence affective polarization, prior patterns of social media engagement can shape this relationship.

    “For instance, Nordbrandt [76], Nyhan et al. [77] observed that while social media usage does not directly influence affective polarization-the individuals' sympathy or antipathy toward specific political parties-prior patterns of social media engagement can shape this relationship.”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [76] Nordbrandt, M. (2019). Affective polarization in the digital age: Testing the direction of the relationship between social media and users’ feelings for out-group parties. New Media & Society. https://doi.org/10.1177/14614448211044393 source

      The Conclusion and discussion reports that starting or increasing social media use did not affect affective polarization over time. It also says prior usage conditioned the reverse relationship—how affective polarization affected later social media use—not an effect of social media use on polarization. The citing sentence blurs that direction. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [77] Nyhan, B., Settle, J., Thorson, E., et al. (2023). Like-minded sources on facebook are prevalent but not polarizing. Nature, 620, 137–144. https://doi.org/10.1038/s41586-023-06297-w source

      The Treatment effects on attitudes section reports no measurable effect on affective polarization from reducing exposure to like-minded Facebook sources. That is narrower than saying social media usage does not directly influence affective polarization. The Discussion says the experiment cannot capture effects of prior Facebook use; it does not establish that prior engagement patterns shape the relationship. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Findingcitation

    User attributes linked to echo chambers include, besides selective exposure, personality traits, fear of isolation and anger, openness, and reflectiveness.

    “These user attributes that are linked to echo chambers include-besides selective exposurepersonality traits (e.g., [16]), fear of isolation and anger (e.g, [104]), openness (e.g., [84]), and reflectiveness (e.g., [93]).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites [16] Boulianne, S., Koc-Michalska, K., & Bimber, B. (2020). Right-wing populism, social media and echo chambers in western democracies. New Media & Society, 22(4), 683–699. https://doi.org/10.1177/1461444819893983 source
    • cites [104] Wollebaek, D., Karlsen, R., Steen-Johnsen, K., & Enjolras, B. (2019). Anger, fear, and echo chambers: The emotional basis for online behavior. Social Media + Society 5(2). https://doi.org/10.1177/2056305119829859 source

      The Discussion and Conclusion says anger can reinforce echo chambers through searches for confirming information. It says fear counteracts that dynamic and reports no relationship between fear and participation in online debates. The cited paper therefore supports the anger portion of [104], but not the claimed link between fear of isolation and echo chambers; the other attributes have separate citations. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [84] Matz, S. C. (2021). Personal echo chambers: Openness-to-experience is linked to higher levels of psychological interest diversity in large-scale behavioral data. Journal of Personality and Social Psychology, 121(6), 1284–1300. source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Homophily is a key driver of content dissemination, and polarization within these communities exacerbates the spread of misinformation.

    “The authors argue that homophily is a key driver of content dissemination and that polarization within these communities exacerbates the spread of misinformation.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [48] Del Vicario, M., Bessi, A., Zollo, F., Petroni, F., Scala, A., Caldarelli, G., Stanley, H. E., & Quattrociocchi, W. (2016). The spreading of misinformation online. Proceedings of the National Academy of Sciences of the United States of America, 113(3), 554–559. source
  • May combine two claims.

    Premisecitation

    Culture or demographics drive polarization and echo chambers.

    “novel research [61,64,92] finds that culture or demographics drive polarization and echo chambers.”
    • Also stated in: § 4.1.3.1 Polarization and fragmentation of the public sphere · plain
      “This finding aligns with findings by Monti et al. [61], Gao et al. [64], and Grusauskaite et al. [92] who find that culture or demographics drive polarization.”
    Quote in the paperNot a substantial claim3 of 3 sources checked
    • cites [61] Monti, C., D’Ignazi, J., Starnini, M., & Morales, G. D. F. (2023). Evidence of demographic rather than ideological segregation in news discussion on reddit. In: Proceedings of the ACM Web Conference 2023 (WWW ’23) (pp. 1–10). ACM, New York, NY, USA. https://doi.org/10.1145/3543507.3583468 source

      The Introduction describes demographic factors as a possible explanation for affective polarization, and the Discussion says the findings support a link between a divided society and polarization. But the Discussion also reports a lack of ideological echo chambers in generalist Reddit news discussions; the paper does not find that culture or demographics drive echo chambers. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [64] Gao, Y., Liu, F., & Gao, L. (2023). Echo chamber effects on short video platforms. Scientific Reports, 13, 6282. https://doi.org/10.1038/s41598-023-33370-1 source

      The Introduction and Conclusion say cultural differences among platform users can hinder the development of echo chambers, so the source supports a cultural influence on echo chambers. It does not establish that culture drives polarization, and its Results describe members’ ages and other characteristics without showing that demographics drive either outcome. No page numbers are available in our copy. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [92] Grusauskaite, K., Carbone, L., Harambam, J., & Aupers, S. (2024). Debating (in) echo chambers: How culture shapes communication in conspiracy theory networks on youtube. New Media & Society, 26(12), 7037–7057. https://doi.org/10.1177/14614448231162585 source

      The Abstract and Conclusion and discussion say that conspiratorial subcultures help explain differing degrees of echo-chamberness across four sampled YouTube comment sections. They do not find that demographics drive echo chambers—the conclusion proposes that as a topic for future research—or that culture drives polarization. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The first two hours of an information cascade are critical for developing opinion clusters.

    “Notably, the first two hours of an information cascade are critical for developing opinion clusters.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [48] Del Vicario, M., Bessi, A., Zollo, F., Petroni, F., Scala, A., Caldarelli, G., Stanley, H. E., & Quattrociocchi, W. (2016). The spreading of misinformation online. Proceedings of the National Academy of Sciences of the United States of America, 113(3), 554–559. source

      The Results and Discussion report that cascade lifetimes peak at about 1–2 hours, while the Abstract says selective exposure generates homogeneous clusters. Neither passage says the first two hours are critical for developing those clusters; the two-hour finding concerns cascade duration, not cluster formation. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Findingcitation

    Dubois and Blank demonstrated that users with more diverse media consumption habits are less likely to become trapped in echo chambers, as varied exposure promotes openness to differing viewpoints, and politically engaged users are particularly resilient to echo chambers.

    “Similarly, Dubois and Blank [12] demonstrated that users with more diverse media consumption habits are less likely to become trapped in echo chambers, as varied exposure to information promotes openness to differing viewpoints and, again, politically engaged users are particularly resilient to echo chambers, with their media choices further mitigating risks of ideological isolation.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [12] Dubois, E., & Blank, G. (2018). The echo chamber is overstated: the moderating effect of political interest and diverse media. Information Communication & Society 21(5, SI), 729–745 https://doi.org/10.1080/1369118X.2018.1428656 source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A small number of highly connected users are responsible for a significant portion of misinformation spread, with 10% of hub communities generating 36% of retweets of false information.

    “For example, Choi et al. [100] found that a small number of highly connected users are responsible for a significant portion of misinformation spread, with 10% of hub communities generating 36% of retweets of false information.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [100] Choi, D., Chun, S., Oh, H., Han, J., & Kwon, T. (2020). Rumor propagation is amplified by echo chambers in social media. Scientific Reports, 10(1), 310. source

      The Introduction and Results report that the top 10% of highly connected rumor echo chambers contributed to 24% of rumor cascades and elicited more than 36% of retweets. The measured units were groups of users, not individual highly connected users, and the paper describes the content as rumors rather than exclusively verified false information. Page numbers are not provided in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    Cross-cutting discussions can paradoxically heighten affective polarization through unfriending, with this effect exacerbated by exposure to incivility on social media.

    “Similarly, Lin et al. [79] demonstrated that cross-cutting discussions can paradoxically heighten affective polarization through unfriending, with this effect exacerbated by exposure to incivility on social media.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [79] Lin, H., Wang, Y., Lee, J., & Kim, Y. (2023). The effects of disagreement and unfriending on political polarization: A moderated-mediation model of cross-cutting discussion on affective polarization via unfriending contingent upon exposure to incivility. Journal of Computer-Mediated Communication, 28(4), 022. https://doi.org/10.1093/jcmc/zmad022 source
  • May combine two claims.

    Findingcitation

    On Weibo, Wang et al. observed that retweeting mechanisms promote polarization, while commenting fosters consensus, highlighting the importance of interaction types in shaping polarization dynamics.

    “On Weibo, Wang et al. [78] observed that retweeting mechanisms promote polarization, while commenting fosters consensus, highlighting the importance of interaction types in shaping polarization dynamics.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [78] Wang, X., Sirianni, A. D., Tang, S., Zheng, Z., & Fu, F. (2020). Public discourse and social network echo chambers driven by socio-cognitive biases. Physical Review X 10(4). https://doi.org/10.1103/PhysRevX.10.041042 source

      The Results and model–data integration sections describe increasingly polarized retweet networks on Twitter during the 2016 U.S. election. A figure caption in Appendix E says that discussion-partner influence can reduce extreme clusters in simulations. The paper does not report observations on Weibo or an empirical comparison showing that commenting fosters consensus. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    YouTube's recommendations amplify far-right content, fostering echo chambers.

    “while YouTube's recommendations amplify far-right content, fostering echo chambers [60,86].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [60] Whittaker, J., Looney, S., Reed, A., & Votta, F. (2021). Recommender systems and the amplification of extremist content. Internet Policy Review 10(3). source

      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 measured
    • cites [86] Kaiser, J., & Rauchfleisch, A. (2020). Birds of a feather get recommended together: Algorithmic homophily in youtube’s channel recommendations in the United States and Germany. Social Media + Society 6(4). https://doi.org/10.1177/2056305120969914 source
  • May combine two claims.

    Premisecitation

    Reducing exposure to like-minded content during the 2020 US presidential election had no measurable effect on polarization in beliefs or attitudes, questioning the causal role of echo chambers in driving societal divides.

    “Furthermore, Nyhan et al. [77] found that although exposure to like-minded content is prevalent on Facebook, reducing such exposure during the 2020 US presidential election had no measurable effect on polarization in beliefs or attitudes.”
    • Also stated in: § 4.1.3.1 Polarization and fragmentation of the public sphere · hedged
      “However, the study by Nyhan et al. [77] demonstrates using a randomized controlled experiment that reducing exposure to like-minded sources may not significantly alter polarization, further questioning the causal role of echo chambers in driving societal divides.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [77] Nyhan, B., Settle, J., Thorson, E., et al. (2023). Like-minded sources on facebook are prevalent but not polarizing. Nature, 620, 137–144. https://doi.org/10.1038/s41586-023-06297-w source
  • May combine two claims.

    Findingcitation

    Reddit's customizable recommendation algorithms encourage exposure to diverse viewpoints, reducing echo chamber effects compared to Facebook.

    “For example, Reddit's customizable recommendation algorithms encourage exposure to diverse viewpoints, reducing echo chamber effects compared to Facebook [17,61,63].”
    Quote in the paperNot a substantial claim3 of 3 sources checked
    • cites [17] Cinelli, M., Morales, G.D.F., Galeazzi, A., Quattrociocchi, W., & Starnini, M. (2021). The echo chamber effect on social media. Proceedings of the National Academy of Sciences of the United States of America 118(9). source

      The Comparative Analysis section (‘News Consumption on Facebook and Reddit’; page unavailable) finds clearer separation by leaning on Facebook, while Reddit users, including those with more extreme leanings, tend to interact with the majority. It does not attribute that difference to Reddit’s customizable recommendation algorithms or establish that those algorithms encourage exposure to diverse viewpoints. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [61] Monti, C., D’Ignazi, J., Starnini, M., & Morales, G. D. F. (2023). Evidence of demographic rather than ideological segregation in news discussion on reddit. In: Proceedings of the ACM Web Conference 2023 (WWW ’23) (pp. 1–10). ACM, New York, NY, USA. https://doi.org/10.1145/3543507.3583468 source

      The Discussion (section 6; page not available in our copy) reports no ideological selective exposure in the Reddit news discussions studied and contrasts generalist Reddit communities with reported echo chambers on Facebook. Background and Related Work (section 2; page not available) also reports higher segregation of news consumption on Facebook than Reddit. The paper does not attribute this difference to customizable recommendation algorithms; it discusses a hypothesis about the platforms’ different structures instead. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [63] Morales, G. D. F., Monti, C., & Starnini, M. (2021). No echo in the chambers of political interactions on reddit. Scientific Reports 11(1). source

      The Discussion reports interactions between opposing political groups on Reddit during the 2016 election and suggests that its forum structure may be less conducive to echo chambers than social networks such as Facebook. It does not attribute that difference to Reddit’s customizable recommendation algorithms; its discussion of Facebook instead emphasizes friendship-network homophily over the news-feed algorithm. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    YouTube 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.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [60] Whittaker, J., Looney, S., Reed, A., & Votta, F. (2021). Recommender systems and the amplification of extremist content. Internet Policy Review 10(3). source
  • May combine two claims.

    Findingcitation

    Many studies found a small echo chamber effect for Republicans, but none for Democrats before and in the aftermath of the 2016 U.S. election.

    “Many studies found a small echo chamber effect for Republicans, but none for Democrats before and in the aftermath of the 2016 U.S. election [70][71][72][73].”
    Quote in the paperNot a substantial claim1 of 4 sources checked
    • cites [70] Justwan, F., Baumgaertner, B., Carlisle, J. E., Clark, A. K., & Clark, M. (2018). Social media echo chambers and satisfaction with democracy among democrats and republicans in the aftermath of the 2016 us elections. Journal of Elections Public Opinion and Parties, 28(4), 424–442. source

      The Conclusion (page unavailable) reports higher satisfaction with democracy among Republicans in social-media echo chambers and no detected effect among Democrats, based on a January 2017 survey. The paper does not establish the same pattern before the election or characterize the Republican effect as small; the Results report predicted satisfaction of 96.6% for Republicans in echo chambers versus 72.0% for those outside them. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [71] Neely, S. R. (2021). Politically motivated avoidance in social networks: A study of facebook and the 2020 presidential election. Social Media + Society 7(4). https://doi.org/10.1177/20563051211055438 source
    • cites [72] Eady, G., Nagler, J., Guess, A., Zilinsky, J., & Tucker, J. A. (2019). How many people live in political bubbles on social media? evidence from linked survey and twitter data. SAGE OPEN 9(1). https://doi.org/10.1177/2158244019832705 source
    • cites [73] Boutyline, A., & Willer, R. (2017). The social structure of political echo chambers: Variation in ideological homophily in online networks. Political Psychology, 38(3), 551–569. https://doi.org/10.1111/pops.12337 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Existing polarization shapes social media usage patterns, rather than social media driving societal polarization.

    “Nordbrandt [76] challenged the assumption that social media drives societal polarization, instead proposing that existing polarization shapes social media usage patterns.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [76] Nordbrandt, M. (2019). Affective polarization in the digital age: Testing the direction of the relationship between social media and users’ feelings for out-group parties. New Media & Society. https://doi.org/10.1177/14614448211044393 source
  • May combine two claims.

    Findingcitation

    On Reddit, studies find minimal evidence of echo chambers due to platform features encouraging cross-cutting exposure.

    “On Reddit, studies find minimal evidence of echo chambers due to platform features encouraging cross-cutting exposure [17,61,63].”
    Quote in the paperNot a substantial claim3 of 3 sources checked
    • cites [17] Cinelli, M., Morales, G.D.F., Galeazzi, A., Quattrociocchi, W., & Starnini, M. (2021). The echo chamber effect on social media. Proceedings of the National Academy of Sciences of the United States of America 118(9). source

      The Comparative Analysis, “News Consumption on Facebook and Reddit” (page not provided), finds less segregation on Reddit and says that even users with more extreme leanings tend to interact with the majority. It does not establish that Reddit’s platform features cause this pattern or encourage cross-cutting exposure. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [61] Monti, C., D’Ignazi, J., Starnini, M., & Morales, G. D. F. (2023). Evidence of demographic rather than ideological segregation in news discussion on reddit. In: Proceedings of the ACM Web Conference 2023 (WWW ’23) (pp. 1–10). ACM, New York, NY, USA. https://doi.org/10.1145/3543507.3583468 source

      The Introduction reports that ideological echo chambers were absent in the studied Reddit news discussions, and the Discussion says the findings strengthen evidence for their absence in generalist Reddit communities. But the Discussion notes that niche subreddits may form echo chambers and presents platform structure as a hypothesis for the difference, not an established cause of cross-cutting exposure. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [63] Morales, G. D. F., Monti, C., & Starnini, M. (2021). No echo in the chambers of political interactions on reddit. Scientific Reports 11(1). source

      The Introduction reports no evidence of echo chambers and more cross-cutting political interactions than expected in the Reddit discussions studied. The Discussion suggests that Reddit’s forum structure might matter, but says further research is needed to determine whether the finding extends beyond the 2016 election; it does not establish that platform features caused the cross-cutting interactions. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Findingcitation

    Content bias varies by platform, suggesting the impact of platform design on echo chamber formation.

    “Nikolov et al. [54] also observe that content bias varies by platform, suggesting the impact of platform design on echo chamber formation.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [54] Nikolov, D., Lalmas, M., Flammini, A., & Menczer, F. (2019). Quantifying biases in online information exposure. Journal of the Association for Information Science and Technology, 70(3), 218–229. https://doi.org/10.1002/asi.24121 source

      The Discussion (p. 15) reports differences in exposure bias across platforms and suggests that differences in platform form and function may help explain them. But the authors say they did not examine content or specific platform mechanisms; the Discussion (p. 17) describes echo-chamber formation as a possible consequence of exposure bias, not a demonstrated effect of platform design. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    Echo chamber detection can occur on individual users, groups, or entire platforms.

    “The difficulties in operationalizing extend to the granularity of echo chamber detection as they can occur on individual users, groups, or entire platforms [111]”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [111] Kratzke, N. (2023). How to find orchestrated trolls? a case study on identifying polarized twitter echo chambers. Computers 12(3). https://doi.org/10.3390/computers12030057 source
  • May combine two claims.

    Findingcitation

    User leaning was also estimated by activity in specific groups, by semantics in the posts, calculation of political slant of visited websites by the user, and shared news URLs with news outlets leaning score.

    “User leaning was also estimated by activity in specific groups (e.g., [59,127,143]), by semantics in the posts (e.g., [94,99,113]), calculation of political slant of visited websites by the user [124], shared news URLs with news outlets leaning score (e.g., [8,96,129]).”
    Quote in the paperNot a substantial claim4 of 7 sources checked
    • cites [59] Rafail, P., & Freitas, I. (2019). Grievance articulation and community reactions in the men’s rights movement online. Social Media + Society 5(2). https://doi.org/10.1177/2056305119841387 source
    • cites [127] Bessi, A., Zollo, F., Del Vicario, M., Scala, A., Caldarelli, G., & Quattrociocchi, W. (2015). Trend of narratives in the age of misinformation. PLOS ONE 10(8). source
    • cites [143] Cinelli, M., Pelicon, A., Mozetic, I., Quattrociocchi, W., Novak, P. K., & Zollo, F. (2021). Dynamics of online hate and misinformation. Scientific Reports 11(1). source

      In Results and discussion, “Users’ behaviour and misinformation” (page unavailable), the paper estimates user leaning from the fraction of comments a user posts on videos from questionable YouTube channels. It does not estimate leaning from shared news URLs or news outlets’ political-leaning scores, the specific method to which this citation is attached. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [94] Cann, T. J. B., Weaver, I. S., & Williams, H. T. P. (2021). Ideological biases in social sharing of online information about climate change. PLOS ONE 16(4). source

      The Methods section (‘Ideological coding of source domains’; page not supplied) says the authors scored the political leaning of domains whose URLs were shared. The Results section (‘Climate media sharing is polarised and politicised’; page not supplied) uses those scores to characterise sharing-network clusters. The paper does not estimate political leaning for individual users, so it supports the cited URL-and-outlet method only at the community level. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [99] Asatani, K., Yamano, H., Sakaki, T., & Sakata, I. (2021). Dense and influential core promotion of daily viral information spread in political echo chambers. Scientific Reports 11(1). source

      The citation to this paper appears in the clause about estimating user leaning from shared news URLs and news outlets’ leaning scores. The Results section (“Independent and steady political echo chambers”; page unavailable) identifies left- and right-leaning communities using reply/retweet relationships and notes liberal and conservative news media among influential accounts. It does not describe scoring shared news URLs or using outlet-leaning scores to estimate users’ leanings; searches for those methods found no supporting passage. (LLM, conf=0.72)

      Experimental — accuracy not yet measured
    • cites [113] Colleoni, E., Rozza, A., & Arvidsson, A. (2014). Echo chamber or public sphere? predicting political orientation and measuring political homophily in twitter using big data. Journal of Communication, 64(2), 317–332. source
    • cites [124] Shore, J., Baek, J., & Dellarocas, C. (2018). Network structure and patterns of information diversity on twitter. Management Information Systems Quarterly, 42(3), 849–972. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Users with ties on social media share partisanship for a party or not.

    “This means that users with ties on social media share partisanship for a party or not[149].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [149] Mosleh, M., Martel, C., Eckles, D., & Rand, D. G. (2021). Shared partisanship dramatically increases social tie formation in a twitter field experiment. Proceedings of the National Academy of Sciences of the United States of America 118(7). source
  • May combine two claims.

    Premisecitation

    The EU DSA grants vetted researchers access to platform data and enables recommendation system audits.

    “which grants vetted researchers access to platform data and enables recommendation system audits [88].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [88] Hartmann, D., Pereira, J. R. L., Streitbörger, C., & Berendt, B. (2024). Addressing the regulatory gap: Moving towards an EU AI audit ecosystem beyond the AIA by including civil society. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Network-level homophily measures the overall homophily of a network to understand the systemic tendencies for like-minded clustering.

    “Network-Level Homophily: Measures the overall homophily of a network to understand the systemic tendencies for like-minded clustering [99,117].”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [99] Asatani, K., Yamano, H., Sakaki, T., & Sakata, I. (2021). Dense and influential core promotion of daily viral information spread in political echo chambers. Scientific Reports 11(1). source

      The Introduction discusses how homophily can emerge, and the Methods section describes clustering users by reply and retweet relationships. Neither section defines or uses a network-level homophily measure to assess overall like-minded clustering (searched: “network-level homophily,” “homophily measure,” and “homophily”). No page numbers are available in our copy. (LLM, conf=0.73)

      Experimental — accuracy not yet measured
    • cites [117] Enjolras, B., & Salway, A. (2022). Homophily and polarization on political twitter during the 2017 Norwegian election. Social Network Analysis and Mining, 13(1), 10. https://doi.org/10.1007/s13278-022-01018-z source
  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    The echo chamber construct is controversial and was ill-defined from the beginning.

    “Firstly, the echo chamber construct is controversial, and researchers claim that it was ill-defined from the beginning and that researchers should either abandon or conceptualize it properly [91].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [91] Mahrt, M. (2019). Beyond Filter Bubbles and Echo Chambers: The Integrative Potential of the Internet. Digital Communication Research 5, 246. Digital Communications Research, Berlin. https://doi.org/10.17174/dcr.v5.0 source

      Section 3.4 reports mixed evidence for online echo chambers, supporting the claim that the idea is contested. Section 4.3 says research lacks a clear threshold for *fragmentation*, but our copy does not say the echo-chamber construct was ill-defined from the beginning or recommend abandoning or reconceptualizing it. No page numbers were available for these passages. (LLM, conf=0.79)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Group-level homophily aggregates the homophily of individual group members to assess group polarization.

    “Group-Level Homophily: Aggregates the homophily of individual group members to assess group polarization [25].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [25] Interian, R., Marzo, R. G., Mendoza, I., & Ribeiro, C. C. Network polarization, filter bubbles, and echo chambers: an annotated review of measures and reduction methods. International Transactions in Operational Research. https://doi.org/10.1111/itor.13224. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Machine learning-based bot detection offers a way to mitigate this issue.

    “Machine learning-based bot detection, as proposed by Rusche [110], and implemented by Choi et al. [100] and Gaumont et al. [120], offers a way to mitigate this issue.”
    Quote in the paperNot a substantial claim3 of 3 sources checked
    • cites [110] Rusche, F. (2022). Few voices, strong echo: Measuring follower homogeneity of politicians’ twitter accounts. New Media & Society, 14614448221099860. https://doi.org/10.1177/14614448221099860 source
    • cites [100] Choi, D., Chun, S., Oh, H., Han, J., & Kwon, T. (2020). Rumor propagation is amplified by echo chambers in social media. Scientific Reports, 10(1), 310. source

      In Methods (Data collection), Choi et al. report using a machine-learning bot detector to identify bot accounts and remove their tweets and retweets when building rumor cascades. This supports the statement that they implemented bot detection, but the paper does not show that it mitigated rumor propagation; the Discussion (Limitation and future work) says detecting and preventing rumor spreads was not covered. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [120] Gaumont, N., Panahi, M., & Chavalarias, D. (2018). Reconstruction of the socio-semantic dynamics of political activist twitter networks-method and application to the 2017 French presidential election. PLOS ONE 13(9). source

      The Abstract (Method) describes automated categorization of Twitter accounts by political affiliation, not bot detection. The Results (Propagation of political information) discuss strategies for mitigating fake news, but do not propose or implement machine-learning-based bot detection. Searches for bot detection, automated accounts, and bots found no passage supporting the attributed claim. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    Latent models can be biased by parameter choices and assumptions and may fall into circular reasoning.

    “Latent models can be biased by parameter choices and assumptions and may fall into circular reasoning, such as inferring political positions from network structures and then using those positions to explain the same structures [155].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [155] Barbera, P. (2013). Birds of the same feather tweet together: Bayesian ideal point estimation using twitter data. SSRN Electronic Journal 23. https://doi.org/10.2139/ssrn.2108098 source

      Section 2.3 (Identification; page unavailable) describes how parameter restrictions and starting values affect identification of the latent scale, and Section 2.1 states the model’s key assumption about whom users follow. The paper does not say these choices bias latent models or warn that inferring positions from a network and then using them to explain that same network is circular reasoning. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    From these, unipartite projections or multiple bipartite graphs are derived to study user-to-user connections or user-content dynamics.

    “From these, unipartite projections or multiple bipartite graphs are derived to study user-to-user connections or user-content dynamics [94,96].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [94] Cann, T. J. B., Weaver, I. S., & Williams, H. T. P. (2021). Ideological biases in social sharing of online information about climate change. PLOS ONE 16(4). source

      Methods > Network construction describes user–URL bipartite networks and a unipartite projection used to analyse sharing patterns. But that projection connects URLs, not users, so this paper does not support the claim that it studies user-to-user connections through the projection. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [96] Del Vicario, M., Zollo, F., Caldarelli, G., Scala, A., & Quattrociocchi, W. (2017). Mapping social dynamics on facebook: The brexit debate. Social Networks, 50, 6–16. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Node-level homophily focuses on individual tendencies to connect with similar users.

    “Node-Level Homophily: Focuses on individual tendencies to connect with similar users (e.g., [73,99]).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [73] Boutyline, A., & Willer, R. (2017). The social structure of political echo chambers: Variation in ideological homophily in online networks. Political Psychology, 38(3), 551–569. https://doi.org/10.1111/pops.12337 source
    • cites [99] Asatani, K., Yamano, H., Sakaki, T., & Sakata, I. (2021). Dense and influential core promotion of daily viral information spread in political echo chambers. Scientific Reports 11(1). source

      The Introduction links homophily to individual cognitive and psychological behaviour, and the Results section on the connected core assumes that users with the same opinion connect with each other. The paper does not identify or define a distinct concept called “node-level homophily,” so it supports the underlying idea but not that specific framing. The indexed copy provides no page numbers for these passages. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    API and scraping studies are predominantly platform-centered, while data donations and tracking data are mainly user-centered.

    “API and scraping studies are predominantly platform-centered, while data donations and tracking data are mainly user-centered [107].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [107] Ohme, J., Araujo, T., Boeschoten, L., Freelon, D., Ram, N., Reeves, B. B., & Robinson, T. N. (2023). Digital trace data collection for social media effects research: Apis, data donation, and (screen) tracking. Communication Methods and Measures 1–18. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Users can be connected in a graph through edges if they are friends or have shared content.

    “Thus, users can be connected in a graph through edges if they are friends (e.g., [136]) or have shared content.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [136] Urman, A. (2019). News consumption of Russian Vkontakte users: Polarization and news avoidance. International Journal of Communication, 13, 5158–5182. source

      The citation is attached to the claim about connecting users who are friends, not the separate claim about shared content. In “Polarization Is Real” (page unavailable), the paper says it examines subscription patterns, not friendship ties; its network description under Figure 1 (page unavailable) defines edges between users and pages they follow. Neither passage addresses edges between users who are friends. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Centrality measures identify influential nodes, such as disseminators (high closeness centrality) or bridges (high betweenness centrality), offering insights into individual roles within echo chambers.

    “Centrality measures identify influential nodes, such as disseminators (high closeness centrality) or bridges (high betweenness centrality), offering insights into individual roles within echo chambers [6,111].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [6] Torregrosa, J., Panizo-Lledot, A., Bello-Orgaz, G., & Camacho, D. (2020). Analyzing the relationship between relevance and extremist discourse in an alt-right network on twitter. Social Network Analysis and Mining 10(1). source
    • cites [111] Kratzke, N. (2023). How to find orchestrated trolls? a case study on identifying polarized twitter echo chambers. Computers 12(3). https://doi.org/10.3390/computers12030057 source

      Materials and Methods (section 2; page unavailable) says centrality measures can identify critical actors in echo chambers and explicitly describes high-betweenness actors as bridges between groups. The paper mentions closeness centrality but does not identify high-closeness actors as disseminators; section 2.2.3 instead calls high-HITS-hub accounts content disseminators. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Metrics like polarity scores measure the distance between users based on their attributes when group membership is unavailable.

    “Metrics like polarity scores measure the distance between users based on their attributes when group membership is unavailable (e.g., [73,100]).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [73] Boutyline, A., & Willer, R. (2017). The social structure of political echo chambers: Variation in ideological homophily in online networks. Political Psychology, 38(3), 551–569. https://doi.org/10.1111/pops.12337 source
    • cites [100] Choi, D., Chun, S., Oh, H., Han, J., & Kwon, T. (2020). Rumor propagation is amplified by echo chambers in social media. Scientific Reports, 10(1), 310. source

      The Results section (‘Properties of rumor echo chambers’; page unavailable) describes polarity scores derived from users’ follows and tweets, and a homogeneity score comparing two users’ political positions. It does not present these scores as a way to measure distance when group membership is unavailable; its comparison explicitly distinguishes echo-chamber members from non-members. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    After removing duplicates and including only peer-reviewed work, 1,051 unique publications were screened for eligibility.

    “This selection resulted in 1,051 unique publications that were then screened for eligibility.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data

    Studies differ in outcomes, focus, construct conceptualization, operationalization, and granularity.

    “We find that studies differ in (1) outcomes, (2) focus, (3) construct conceptualization and (4) operationalization, and (5) granularity.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    A total of 1,051 studies were screened based on title, excluding 655 studies that did not meet the three criteria.

    “A total of 1,051 studies were screened based on title, excluding 655 studies that did not meet the three criteria.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Studies based on homophily and computational social science methods often support the echo chamber hypothesis, while research on content exposure and broader media environments, such as surveys, tends to challenge it.

    “Studies based on homophily and computational social science methods often support the echo chamber hypothesis, while research on content exposure and broader media environments, such as surveys, tends to challenge it.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    The review of 129 studies identifies variations in measurement approaches, as well as regional, political, cultural, and platform-specific biases, as key factors contributing to the lack of consensus.

    “The review of 129 studies identifies variations in measurement approaches, as well as regional, political, cultural, and platform-specific biases, as key factors contributing to the lack of consensus.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The 129 studies included in the systematic review were all published between 2014 and 2023.

    “The 129 studies included in the systematic review were all published between 2014 and 2023, as Fig. 4a illustrates.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Database searches yielded a total of 1,706 results.

    “Database searches yielded a total of 1,706 results.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. May combine two claims.

    Findingnone given

    Group behavior, cultural influences, instant messaging platforms, and short video platforms remain underexplored.

    “Group behavior, cultural influences, instant messaging platforms, and short video platforms remain underexplored.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    514 duplicates were removed.

    “514 duplicates were removed.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    From an initial set of 1,706 studies, 129 studies were selected based on criteria.

    “From an initial set of 1,706 studies, we selected these 129 studies based on criteria explained in Sect.3.4.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    The survey by Dubois et al. found that political involvement and media variety reduce the risk of being in an echo chamber.

    “The survey by Dubois et al. [65] found that political involvement and media variety reduce the risk of being in an echo chamber.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [65] Dubois, E., Minaeian, S., Paquet-Labelle, A., & Beaudry, S. (2020). Who to trust on social media: How opinion leaders and seekers avoid disinformation and echo chambers. Social Media + Society 6(2). https://doi.org/10.1177/2056305120913993 source
  • May combine two claims.

    Findingreasoning

    Recommendation algorithms significantly influence echo chambers, but gaps remain in understanding the interplay between moderation practices and echo chamber dynamics.

    “While evidence suggests that recommendation algorithms significantly influence echo chambers, gaps remain in understanding the interplay between moderation practices and echo chamber dynamics.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Findingown data

    After analysis of studies, the authors differentiate between single-user, group, platform, cross-platform, and holistic granularity.

    “After analysis of studies, we differentiate between single-user, group, platform, cross-platform, and holistic.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    Fragmentation, measured through the size and density of communities across entire platforms, has been comparatively understudied.

    “On the other hand, fragmentation, measured through the size and density of communities across entire platforms, has been comparatively understudied.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingcitation

    On Facebook, Beam et al. found that users exposed to newsfeeds experienced depolarization over time, suggesting that social media could reduce rather than reinforce ideological segregation.

    “On Facebook, Beam et al. [74] found that users exposed to newsfeeds experienced depolarization over time, suggesting that social media could reduce rather than reinforce ideological segregation.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [74] Beam, M. A., Hutchens, M. J., & Hmielowski, J. D. (2018). Facebook news and (de)polarization: Reinforcing spirals in the 2016 us election. Information, Communication & Society, 21(7), 940–958. https://doi.org/10.1080/1369118X.2018.1444783 source
  • May combine two claims.

    Findingnone given

    14 studies in the corpus investigate the relationship between echo chambers and extremism, examining how homophily and algorithmic amplification contribute to radicalization.

    “14 studies in the corpus investigate the relationship between echo chambers and extremism, examining how homophily and algorithmic amplification contribute to radicalization.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Findingnone given

    Four key concepts are integral to echo chamber conceptualizations: homophily, content exposure, individual user behaviors (such as selective exposure, confirmation bias or fear), and group behaviors (including exclusion of outsiders and collective unfriending).

    “We identified four key concepts integral to echo chamber conceptualizations: (1) homophily, (2) content exposure, (3) individual user behaviors, such as selective exposure, confirmation bias or fear, and (4) group behaviors, including exclusion of outsiders and collective unfriending.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingnone given

    Few papers looked at the specific group behavior of these groups but mainly examined homophily over time and information flow to the group as opposed to outside the group.

    “However, few papers looked at the specific group behavior of these groups but mainly examined homophily over time and information flow to the group as opposed to outside the group.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingcitation

    Eady et al. and Barbera et al. observed significant ideological overlap among the most liberal and conservative users, contradicting the assumption of rigid polarization.

    “Similarly, Eady et al. [72] and Barbera et al. [75] observed significant ideological overlap among the most liberal and conservative users, contradicting the assumption of rigid polarization.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [72] Eady, G., Nagler, J., Guess, A., Zilinsky, J., & Tucker, J. A. (2019). How many people live in political bubbles on social media? evidence from linked survey and twitter data. SAGE OPEN 9(1). https://doi.org/10.1177/2158244019832705 source
    • cites [75] Barbera, P., Jost, J. T., Nagler, J., Tucker, J. A., & Bonneau, R. (2015). Tweeting from left to right: Is online political communication more than an echo chamber? Psychological Science, 26(10), 1531–1542. https://doi.org/10.1177/0956797615594620 source
  • May combine two claims.

    Findingnone given

    Selective exposure, demographics, emotions, and personality traits are key factors in echo chamber formation.

    “Selective exposure, demographics, emotions, and personality traits have been identified as key factors in echo chamber formation”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingreasoning

    The relationship between societal polarization, fragmentation, and echo chambers is complex and often correlational rather than causal.

    “The relationship between societal polarization, fragmentation, and echo chambers is complex and often correlational rather than causal.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    Recommendation systems and content moderation are frequently cited as primary drivers of echo chambers due to their role in shaping user content exposure.

    “recommendation systems and content moderation are frequently cited as primary drivers of echo chambers due to their role in shaping user content exposure.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    Many studies put more focus on the content that an individual sees through their news feed curated by recommendation systems.

    “This is why many studies put more focus on the content that an individual sees through their news feed curated by recommendation systems.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Polarization may stem from other factors, such as traditional media, cultural differences, demographics, or other offline influences, complicating the attribution of causality solely to social media.

    “However, novel studies from 2023 also highlight that polarization may stem from other factors, such as traditional media, cultural differences, demographics, or other offline influences, complicating the attribution of causality solely to social media.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Twenty-three studies in the corpus address the connection between echo chambers and misinformation, with seven focusing explicitly on misinformation in the context of echo chambers.

    “Twenty-three studies in the corpus address this connection, with seven focusing explicitly on misinformation in the context of echo chambers.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Such an echo chamber conceptualization is hardly reflected in the corpus, although there is research that examines particular group behavior and presents it as echo chamber-specific.

    “However, such an echo chamber conceptualization is hardly reflected in the corpus, although there is research that examines particular group behavior and presents it as echo chamber-specific.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    It remains unclear how selective exposure and recommendation systems interact with each other.

    “it remains unclear how selective exposure and recommendation systems interact with each other”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingcitation

    Facebook users tend to consume more partisan news than Reddit users, who encounter greater content diversity.

    “Comparative studies, such as Kitchens et al. [24], found that Facebook users tend to consume more partisan news than Reddit users, who encounter greater content diversity.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [24] Kitchens, B., Johnson, S. L., & Gray, P. (2020). Understanding echo chambers and filter bubbles: The impact of social media on diversification and partisan shifts in news consumption. MIS Quarterly, 44(4), 1619–1649. source
  • May combine two claims.

    Findingnone given

    User engagement has been found to correlate positively with echo chambers and political affiliation.

    “User engagement has been found to correlate positively with echo chambers and political affiliation.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingreasoning

    The majority of results are consistent with the echo chamber hypothesis that echo chambers contribute to both polarization and societal fragmentation.

    “Despite diverse operationalizations, the majority of results are consistent with the echo chamber hypothesis: echo chambers contribute to both polarization and societal fragmentation.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingnone given

    Although group behaviors play a role in echo chamber formation, few studies have investigated them comprehensively or as antecedents of the construct.

    “Although group behaviors play a role in echo chamber formation, few studies have investigated them comprehensively or as antecedents of the construct.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based).

    Findingnone given

    Previous studies have focused on either selective exposure or recommendation systems, not their interaction.

    “given that previous studies have focused on one or the other.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Out of all survey studies, 17 looked at general social media usage or the whole media diet, while only two looked at specific platforms.

    “Out of all survey studies, 17 looked at general social media usage or the whole media diet, while only two looked at specific platforms.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingcitation

    In the identified studies, nodes often represent users and edges denote interactions between users and interaction of users with content such as posts or hyperlinks to news pages.

    “In the identified studies, nodes often represent users and edges denote interactions between users and interaction of users with content such as posts or hyperlinks to news pages (e.g., [108]).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [108] Aruguete, N., Calvo, E., & Ventura, T. (2023). News by popular demand: Ideological congruence, issue salience, and media reputation in news sharing(1). International Journal of Press-Politics. https://doi.org/10.1177/19401612211057068 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    About half of the survey studies were conducted in the USA, a total of 8.

    “About half of the surveys were conducted in the USA (a total of 8), and only 5 of these studies addressed the echo chamber hypothesis directly.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Each user can be characterized by a vector of node attributes, such as demographic information, interests, or activity patterns.

    “Each user can be characterized by a vector of node attributes, 8 such as demographic information, interests, or activity patterns.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingreasoning

    While these metrics provide user-level insights, they do not directly capture broader interaction patterns or group dynamics.

    “While these metrics provide user-level insights, they do not directly capture broader interaction patterns or group dynamics.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data

    Studies using CSS methods typically conceptualize echo chambers as attribute-based homophilic structures, whereas surveys and experimental studies focus on content exposure and user behavior.

    “For instance, studies using CSS methods typically conceptualize echo chambers as attribute-based homophilic structures, whereas surveys and experimental studies focus on content exposure and user behavior.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    The general procedure was to build a graph for every time-dependent sample and use interaction (structural data sets) or semantic networks (content-considering data sets).

    “Based on these two types of data sets, the general procedure was to build a graph for every time-dependent sample as social networks are dynamic networks [142] and use interaction (structural data sets) or semantic networks (content-considering data sets)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [142] Light, R., & Moody, J. (2021). 16network basics: Points, lines, and positions. In The Oxford handbook of social networks. Oxford University Press. https://doi.org/10.1093/oxfordhb/9780190251765.013.2 source
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    API restrictions have made access more challenging in recent years.

    “However, API restrictions have made access more challenging in recent years.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingnone given

    Purely structural data sets consist of interactions between users such as 'likes', 'posts', 'comments', 'friendship', 'shares', etc.; contentconsidering data sets use the content of 'posts' and 'comments' to gain insights into the users political leaning, polarization, radicalism or other attributes.

    “The former data sets consist of interactions between users such as 'likes', 'posts', 'comments','friendship', 'shares', etc.; the latter use the content of 'posts' and 'comments' to gain insights into the users political leaning, polarization, radicalism or other attributes.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    The underlying data sets can be classified into API and scraping data, crowdsourced or donated data, and tracking data.

    “The underlying data sets can be classified into API and scraping data, crowdsourced or donated data, and tracking data.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Survey studies use between 5 and 41 items to gather data from a participant pool of 198 to 11,052 individuals.

    “The studies use between 5 and 41 items to gather data from a participant pool of 198 to 11,052 individuals.”
    Quote in the paperNot a substantial claim
  • The quote only partly states this claim.

    Findingown data

    Only 5 of the survey studies addressed the echo chamber hypothesis directly.

    “About half of the surveys were conducted in the USA (a total of 8), and only 5 of these studies addressed the echo chamber hypothesis directly.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    The next methodological step for most of the social data methods was to use a community detection algorithm.

    “The next methodological step for most of the social data methods was to use a community detection algorithm.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    The edges can be weighted by the strength of the social tie between users, such as the frequency, intensity of interactions, or a friendship tie.

    “The edges can be weighted by the strength of the social tie between users, such as the frequency, intensity of interactions, or a friendship tie.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    In the reviewed literature, many studies identify associations but few establish causal relationships, such as whether echo chambers amplify polarization or whether pre-existing polarization fosters echo chambers.

    “While many studies identify associations, few establish causal relationships, such as whether echo chambers amplify polarization or whether pre-existing polarization fosters echo chambers.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingreasoning

    The user is connected to posts or news pages that they have shared, thus also creating a semantic network.

    “At the same time, the user is connected to posts or news pages that they have shared, thus also creating a semantic network.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    There is another distinction between the underlying observational trace data sets for echo chamber research: purely structural data (interaction-based) and contentconsidering data sets.

    “We find another distinction between the underlying observational trace data sets for echo chamber research: purely structural data (interaction-based) and contentconsidering data sets.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Ten experiments are part of the review corpus.

    “Ten experiments are part of the corpus.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    To assess the similarity between different users in communities, different metrics are used.

    “To asses the similarity between different users in communities, different metrics are used.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Studies that included data donated by users included additional information to the traces, but were smaller in size.

    “Studies that included data donated by users included additional information to the traces, but were smaller in size.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Out of all the analyzed studies in the review corpus, 20 were surveys.

    “Out of all the analyzed studies, 20 were surveys.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Data consisted of posts, comments, likes, and other digital traces.

    “Data consisted of posts, comments, likes, and other digital traces.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Findingnone given

    Adjustable recommender systems like those tested on Reddit allow users to customize content diversity, reducing algorithmic reinforcement of homogeneous content and introducing contrasting perspectives.

    “Adjustable recommender systems like those tested on Reddit allow users to customize content diversity, reducing algorithmic reinforcement of homogeneous content and introducing contrasting perspectives.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data

    Most studies affirming the echo chamber hypothesis are conducted in the United States or use data concerning the United States population and are not representative of other regions.

    “Concurrent with previous research, we find that most studies affirming the echo chamber hypothesis are conducted in the United States or use data concerning the United States population and are not representative of other regions.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Most of the studies look at a certain event, such as an election, to investigate emerging echo chambers around that event.

    “most of the studies look at a certain event, such as an election to investigate emerging echo chambers around that event.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Content-considering data sets either had to be labeled, cleaned, or had to apply resource-intensive Machine Learning (ML) algorithms to make sense of their data.

    “whereas content-considering data sets either had to be labeled, cleaned or had to apply resource-intensive Machine Learning (ML) algorithms to make sense of their data.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Findingnone given

    To detect and analyze echo chambers, a variety of metrics are employed, categorized into interaction-based metrics, content-considering metrics, homophily and polarization measures, and modularity measures.

    “To detect and analyze echo chambers, a variety of metrics are employed, categorized into interaction-based metrics, content-considering metrics, homophily”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    Different amounts of users and data were used for the analysis.

    “Different amounts of users and data were used for the analysis”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Data gathering periods differ among studies.

    “Data gathering periods differ among studies as well”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    Polarization and homophily measures are frequently calculated on these networks to assess ideological clustering.

    “Polarization and homophily measures are frequently calculated on these networks to assess ideological clustering.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Studies using homophily as a conceptualization tend to have affirming results on the echo chamber hypothesis, and studies using context exposure tend to have negative findings.

    “Here again, studies using homophily as a conceptualization tend to have affirming results on the echo chamber hypothesis, and studies using context exposure tend to have negative findings.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    More studies from the US and UK affirm the echo chamber hypothesis and less from countries such as Germany, France, and the Netherlands.

    “We find that more studies from the US and UK affirm the echo chamber hypothesis and less from countries such as Germany, France, and the Netherlands.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingnone given

    Both Masip et al. and Beam et al. found no echo chambers or polarization through social media, contrary to homophily studies.

    “Interestingly, both studies found no echo chambers or polarization through social media, contrary to homophily studies.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingreasoning

    Research on platforms such as Instagram, WhatsApp, Telegram, TikTok, and WeChat is notably absent, largely due to challenges in data accessibility.

    “Research on platforms such as Instagram, WhatsApp, Telegram, TikTok, and WeChat is notably absent, largely due to challenges in data accessibility.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Some content-considering data sets first transformed the network into a weighted, undirected network by computing pairwise similarities between nodes of the same type.

    “Some of the content-considering data sets first transformed the network into a weighted, undirected network by computing the pairwise similarities between nodes of the same type (e.g., similarity between users based on their shared interactions with content or friendship ties).”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    Homophily and polarization metrics are used interchangeably in many studies to evaluate the similarity between users within echo chambers.

    “Homophily and Polarization Metrics.These are used interchangeably in many studies to evaluate the similarity between users within echo chambers.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    In the context of the bipartite graph B, these algorithms are used to detect communities of users who are more likely to interact with content items within their community than with content items outside their community.

    “In the context of the bipartite graph B, these algorithms are used to detect communities of users who are more likely to interact with content items within their community than with content items outside their community.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Some used scraping or tracking via plugins (e.g., Bing toolbar, YouGov).

    “Some used scraping or tracking via plugins (e.g., Bing toolbar, YouGov).”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    There were also works that examined longer time spans.

    “There were also works that examined longer time spans.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    Most CSS studies used a form of social network analysis and followed a specific procedure.

    “In general, most CSS studies used a form of social network analysis and followed this procedure:”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Findingreasoning

    Echo chambers can still emerge under specific conditions, such as heightened political interest, selective exposure tendencies, or high user activity.

    “However, they also find that echo chambers can still emerge under specific conditions, such as heightened political interest, selective exposure tendencies, or high user activity.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    The size of the data sets varied by platform and by study.

    “The size of the data sets varied by platform and by study as Fig. 7 in the”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingreasoning

    Studies employing CSS methods are more likely to identify echo chambers, while surveys and experiments tend to produce mixed or less conclusive results.

    “Studies employing CSS methods are more likely to identify echo chambers, while surveys and experiments tend to produce mixed or less conclusive results.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Most survey studies and experiments did not research one platform in particular.

    “It is important to note that most survey studies and experiments did not research one platform in particular and are therefore not considered in this plot”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Findingreasoning

    Figure 6b illustrates a clear relationship between methods and outcomes.

    “Figure 6b illustrates a clear relationship between methods and outcomes.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingnone given

    Content-considering metrics estimate user attributes, such as political leanings, or analyze cross-cutting content exposure to understand how individuals engage with ideologically similar or diverse content.

    “Content-Considering Metrics.They estimate user attributes, such as political leanings, or analyze cross-cutting content exposure to understand how individuals engage with ideologically similar or diverse content.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Interaction-based methods rely heavily on centrality measures to identify influential users and assess the structural dynamics of networks.

    “Interaction-based methods.These metrics rely heavily on centrality measures to identify influential users and assess the structural dynamics of networks:”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Study design and conductown data

    After codebook establishment, the third coder independently coded 19 random studies (roughly 15% sample), and ICR was substantial (Cohen's = 0.66).

    “After the codebook was established through an initial coding round and discussions between the first author and second author, the third coder independently coded 19 random studies (roughly a 15 % sample [39]).Here, ICR was substantial (Cohen's = 0.66foot_2 ).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [39] O’Connor, C., & Joffe, H. (2020). Intercoder reliability in qualitative research: Debates and practical guidelines. International Journal of Qualitative Methods, 19, 1609406919899220. https://doi.org/10.1177/1609406919899220 source
  • May combine two claims.

    Study design and conductreasoning

    The review only used English keywords and included studies written in English, which may exclude studies relating to non-English speaking countries and the Global South.

    “In this review, we only used English keywords and included studies written in English for transparency and reproducibility reasons.This means that studies relating to certain countries might be excluded from our corpus and there could be results relating to non-English speaking countries and the Global South that are not included in our analysis.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    Standardized methods for search, evaluation, and selection of studies reduce subjective influences.

    “We use standardized methods for search, evaluation, and selection of studies reduce subjective influences [30].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [30] Biondi-Zoccai, G., Lotrionte, M., Landoni, G., & Modena, M. G. (2011). The rough guide to systematic reviews and meta-analyses. HSR Proceedings in Intensive Care and Cardiovascular Anesthesia, 3(3), 161–173.
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    There is no evidence that social media increases support for right-wing populism.

    “Boulianne et al. [16] found no evidence that social media increases support for right-wing populism”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [16] Boulianne, S., Koc-Michalska, K., & Bimber, B. (2020). Right-wing populism, social media and echo chambers in western democracies. New Media & Society, 22(4), 683–699. https://doi.org/10.1177/1461444819893983 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Network relevance is associated with extremist content, highlighting the role of user connections in spreading radical ideologies.

    “Similarly, Torregrosa et al. [6] observed that network relevance is associated with extremist content, highlighting the role of user connections in spreading radical ideologies.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [6] Torregrosa, J., Panizo-Lledot, A., Bello-Orgaz, G., & Camacho, D. (2020). Analyzing the relationship between relevance and extremist discourse in an alt-right network on twitter. Social Network Analysis and Mining 10(1). source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationcitation

    Weak ties expose users to radical ideas, but the lack of reciprocal connections may limit deeper engagement.

    “While these weak ties expose users to radical ideas, the lack of reciprocal connections may limit deeper engagement.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [101] Wolfowicz, M., Weisburd, D., & Hasisi, B. (2023). Examining the interactive effects of the filter bubble and the echo chamber on radicalization. Journal of Experimental Criminology. source
  • May combine two claims.

    Premisecitation

    Challenge avoidance and reinforcement seeking are cognitive mechanisms that explain the persistence of polarized behavior.

    “Challenge avoidance and reinforcement seeking: Both are cognitive mechanisms that explain the persistence of polarized behavior.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Significant ideological differences in self-censorship practices and fears of isolation exist, and political identity influences individuals' willingness to engage in public discourse.

    “Burnett et al. [69] highlights significant ideological differences in self-censorship practices and fears of isolation, showing how political identity influences individuals' willingness to engage in public discourse”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [69] Burnett, A., Knighton, D., & Wilson, C. (2022). The self-censoring majority: How political identity and ideology impacts willingness to self-censor and fear of isolation in the united states. Social Media + Society 8(3). source
  • May combine two claims.

    Premisecitation

    Reinforcement-seeking amplifies group coherence by encouraging users to engage with content that aligns with their preexisting beliefs, while challenge avoidance leads users to ignore dissenting information, deepening polarization.

    “Reinforcement-seeking amplifies group coherence by encouraging users to engage with content that aligns with their preexisting beliefs, while challenge avoidance leads users to ignore dissenting information, deepening polarization.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Interpretationcitation

    This selective communication reinforces echo chambers by deepening ideological isolation.

    “This selective communication reinforces echo chambers by deepening ideological isolation.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationcitation

    This structural advantage makes conservative groups more prone to echo chambers and potential radicalization.

    “This structural advantage makes conservative groups more prone to echo chambers and potential radicalization.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationcitation

    Early cascades and densely connected nodes are important in amplifying misinformation.

    “These findings highlight the importance of early cascades and densely connected nodes in amplifying misinformation.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Platform dynamics can invert traditional silencing mechanisms, allowing a vocal minority to overshadow the silent majority, particularly in ideologically polarized contexts.

    “This inversion allows a vocal minority to overshadow the silent majority, particularly in ideologically polarized contexts.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [69] Burnett, A., Knighton, D., & Wilson, C. (2022). The self-censoring majority: How political identity and ideology impacts willingness to self-censor and fear of isolation in the united states. Social Media + Society 8(3). source
    • cites [80] Powers, E., Koliska, M., & Guha, P. (2019). “Shouting matches and echo chambers”: Perceived identity threats and political self-censorship on social media. International Journal of Communication, 13, 3630–3649.

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Sunstein emphasized that technology has the potential to increase fragmentation on a larger scale, with people no longer living separately but rather forming groups where those with similar ideological preferences associate exclusively with one another.

    “Both in 2001 [7] and then again in 2017 [10], Sunstein emphasized that technology has the potential to increase fragmentation on a larger scale, with people no longer living separately but rather forming groups where those with similar ideological preferences associate exclusively with one another.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [7] Sunstein, C. (2001). Republic.com. Princeton University Press

      Not checked in the free run.

    • cites [10] Sunstein, C. (2017). Republic: Divided democracy in the age of social media. Princeton University Press. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Exposure to counter-attitudinal news on Facebook could promote depolarization.

    “Contrarily, Beam et al. [74] reported that exposure to counter-attitudinal news on Facebook could promote depolarization, challenging assumptions about affective polarization.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [74] Beam, M. A., Hutchens, M. J., & Hmielowski, J. D. (2018). Facebook news and (de)polarization: Reinforcing spirals in the 2016 us election. Information, Communication & Society, 21(7), 940–958. https://doi.org/10.1080/1369118X.2018.1444783 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    According to Pariser, personalization technology is the underlying mechanism of echo chambers, and it will show users information that confirms their own opinions at the expense of information that challenges them.

    “According to Pariser [9], personalization technology is the underlying mechanism of echo chambers, and he contends that this technology will show users information that confirms their own opinions at the expense of information that challenges them.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [9] Pariser, E. (2011). The filter bubble: What the internet is hiding from you. The Penguin Group. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Initial network creation by recommendation systems can embed users in echo chambers depending on their initial interactions.

    “Hilbert et al. [87] emphasized the influence of initial network creation by recommendation systems, which can embed users in echo chambers depending on their initial interactions.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [87] Hilbert, M., Ahmed, S., Cho, J., Liu, B., & Luu, J. (2018). Communicating with algorithms: A transfer entropy analysis of emotions-based escapes from online echo chambers. Communication Methods and Measures, 12(4), 260–275. https://doi.org/10.1080/19312458.2018.1479843 source
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Group behaviors play a role in echo chamber formation.

    “Although group behaviors play a role in echo chamber formation”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Nguyen argues that an echo chamber is a social epistemic structure in which other relevant voices have been actively discredited.

    “Nguyen [102] argues that an echo chamber is”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [102] Nguyen, C. T. (2020). Echo chambers and epistemic bubbles. Episteme, 17(2), 141–161. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    Online behavior often reflects existing offline communities rather than driving polarization or radicalization.

    “suggesting that online behavior often reflects existing offline communities rather than driving polarization or radicalization.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    College students avoid expressing political opinions online to protect their civic identity, reflecting a strategic approach to maintain social harmony in ideologically congruent networks.

    “Accordingly, Powers et al. [80] observed that college students avoid expressing political opinions online to protect their civic identity, reflecting a strategic approach to maintain social harmony in ideologically congruent networks.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [80] Powers, E., Koliska, M., & Guha, P. (2019). “Shouting matches and echo chambers”: Perceived identity threats and political self-censorship on social media. International Journal of Communication, 13, 3630–3649.

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The overall structure of echo chambers in Nguyen's account is built on creating a substantial trust imbalance between members and non-members so outsiders are no longer taken seriously.

    “The overall structure of echo chambers in his account is built on creating a substantial trust imbalance between members and non-members so outsiders are no longer taken seriously [102].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [102] Nguyen, C. T. (2020). Echo chambers and epistemic bubbles. Episteme, 17(2), 141–161. source
  • May combine two claims.

    Interpretationreasoning

    User behavior and individual attributes play significant roles in echo chamber formation, and they offer pathways to mitigate such effects through active engagement and media diversity.

    “These findings suggest that while user behavior and individual attributes play significant roles in echo chamber formation, they also offer pathways to mitigate such effects through active engagement and media diversity.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Exposure to diverse media and political engagement can counteract the tendency to choose content that aligns with existing opinions, reducing echo chamber risks.

    “However, as Dubois et al. [65] notes, exposure to diverse media and political engagement can counteract this tendency, reducing echo chamber risks.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [65] Dubois, E., Minaeian, S., Paquet-Labelle, A., & Beaudry, S. (2020). Who to trust on social media: How opinion leaders and seekers avoid disinformation and echo chambers. Social Media + Society 6(2). https://doi.org/10.1177/2056305120913993 source
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Behaviors such as avoidance, unfriending, and discreditation are mechanisms that reinforce group cohesion by excluding opposing views.

    “Behaviors such as avoidance, unfriending, and discreditation are mechanisms that reinforce group cohesion by excluding opposing views.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The isolation of the individual has negative effects, as it leads to epistemic bubbles where personal ideas go unchallenged and untested.

    “The isolation of the individual has negative effects, as it leads to epistemic bubbles where personal ideas go unchallenged and untested [102].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [102] Nguyen, C. T. (2020). Echo chambers and epistemic bubbles. Episteme, 17(2), 141–161. source
  • May combine two claims.

    Premisecitation

    Openness to experience and extraversion correlate with greater exposure to diverse viewpoints, while introversion and conscientiousness are linked to like-minded discussions.

    “Studies found that traits such as openness to experience and extraversion correlate with greater exposure to diverse viewpoints, while introversion and conscientiousness are linked to like-minded discussions [84,85].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [84] Matz, S. C. (2021). Personal echo chambers: Openness-to-experience is linked to higher levels of psychological interest diversity in large-scale behavioral data. Journal of Personality and Social Psychology, 121(6), 1284–1300. source
    • cites [85] Boulianne, S., & Koc-Michalska, K. (2022). The role of personality in political talk and like-minded discussion. International Journal of Press-Politics, 27(1), 285–310. https://doi.org/10.1177/1940161221994096 source
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    These communities might have been polarized from the beginning.

    “However, these communities might have been polarized from the beginning.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning

    Misinformation is intricately linked to echo chambers, with highly connected and influential users driving both phenomena.

    “In summary, misinformation is intricately linked to echo chambers, with highly connected and influential users driving both phenomena.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Political leanings and perceived credibility influence avoidance behaviors, particularly among Republicans, during the 2020 U.S. elections.

    “Neely [71] found that political leanings and perceived credibility influence avoidance behaviors, particularly among Republicans, during the 2020 U.S. elections.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [71] Neely, S. R. (2021). Politically motivated avoidance in social networks: A study of facebook and the 2020 presidential election. Social Media + Society 7(4). https://doi.org/10.1177/20563051211055438 source
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Interpretationreasoning

    Mixed-methods approaches, which combine trace data, surveys, and experiments, offer a promising pathway to uncovering the nuanced mechanisms driving echo chambers.

    “Mixed-methods approaches, which combine trace data, surveys, and experiments, offer a promising pathway to uncovering the nuanced mechanisms driving echo chambers.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationreasoning

    These communities can be interpreted as echo chambers, where users are exposed to information that reinforces their existing beliefs and opinions, if these communities are communities of like-minded people with similar attributes.

    “These communities can be interpreted as echo chambers, where users are exposed to information that reinforces their existing beliefs and opinions, if these communities are communities of like-minded people with similar attributes.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Study design and conductreasoning

    These efforts improved consistency, resulting in a Cohen's value of 0.66.

    “These efforts improved consistency, resulting in a Cohen's value of 0.66.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Observational data can identify associations but cannot establish causality.

    “Observational data can identify associations but cannot establish causality.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationnone given

    CSS methods are effective for identifying patterns and relationships within networks but often fail to account for the social, cultural, and political contexts that shape these networks.

    “CSS methods are effective for identifying patterns and relationships within networks but often fail to account for the social, cultural, and political contexts that shape these networks.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Premisecitation

    Self-reported data often captures perceived rather than actual homophily, which can lead to underestimation of polarization.

    “Self-reported data often captures perceived rather than actual homophily, which can lead to underestimation of polarization [73].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [73] Boutyline, A., & Willer, R. (2017). The social structure of political echo chambers: Variation in ideological homophily in online networks. Political Psychology, 38(3), 551–569. https://doi.org/10.1111/pops.12337 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning

    Disagreements were thoroughly discussed, and the codebook was refined during the coding process.

    “To address this, disagreements were thoroughly discussed, and the codebook was refined during the process.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Most systematic reviews do not measure or report inter-coder reliability (ICR), nor do they provide transparency in how their coding processes are executed.

    “It is worth noting that most systematic reviews do not measure or report ICR, nor do they provide transparency in how their coding processes are executed [165].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [165] Belur, J., Tompson, L., Thornton, A., & Simon, M. (2021). Interrater reliability in systematic review methodology: Exploring variation in coder decision-making. Sociological Methods & Research, 50(2), 837–865. source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    The initial agreement between the first and third coders was moderate.

    “The initial agreement between the first and third coders was moderate.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    The differences by platform could be related to the platforms' API access restrictions.

    “The differences by platform could be related to the platforms' API access restrictions.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    EI-Index calculates relative homophily, capturing the balance between in-group and out-group ties.

    “EI-Index: Calculates relative homophily, capturing the balance between in-group and out-group ties [86,114].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [86] Kaiser, J., & Rauchfleisch, A. (2020). Birds of a feather get recommended together: Algorithmic homophily in youtube’s channel recommendations in the United States and Germany. Social Media + Society 6(4). https://doi.org/10.1177/2056305120969914 source
    • cites [114] Bruns, A. (2017). Echo chamber? what echo chamber? reviewing the evidence. In 6th Biennial future of journalism conference (FOJ17). source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    The lack of research outside the US and Global North may be due to limits of literature searches in systematic reviews or difficult data situations.

    “This may be due to the limits of literature searches in systematic reviews or the difficult data situation.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Social networks are dynamic networks.

    “as social networks are dynamic networks [142]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [142] Light, R., & Moody, J. (2021). 16network basics: Points, lines, and positions. In The Oxford handbook of social networks. Oxford University Press. https://doi.org/10.1093/oxfordhb/9780190251765.013.2 source
  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationnone given

    The focus on single platforms restricts the generalizability of findings and overlooks cross-platform dynamics.

    “One issue is the focus on single platforms, which restricts the generalizability of findings and overlooks crossplatform dynamics.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationreasoning

    These platforms lack open APIs, introducing a significant data accessibility bias.

    “These platforms lack open APIs, introducing a significant data accessibility bias.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Causal inference remains one of the most significant challenges in CSS.

    “Causal inference remains one of the most significant challenges in CSS.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Interpretationreasoning

    These steps enhance the reproducibility and reliability of the findings.

    “These steps enhance the reproducibility and reliability of the findings.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Premisecitation

    The echo chamber concept does not represent any observable outcome because it describes a state of absence, namely the absence of an idealized model of a deliberative public sphere such as the Habermasian democratic model.

    “This is largely because the concept does not represent any observable outcome since “echo chambers” describe a state of absence, namely the absence of an idealized model of a deliberative public sphere such as the Habermasian democratic model [24,114].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [24] Kitchens, B., Johnson, S. L., & Gray, P. (2020). Understanding echo chambers and filter bubbles: The impact of social media on diversification and partisan shifts in news consumption. MIS Quarterly, 44(4), 1619–1649. source
    • cites [114] Bruns, A. (2017). Echo chamber? what echo chamber? reviewing the evidence. In 6th Biennial future of journalism conference (FOJ17). source
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    The interplay between homophily and selective exposure may be more critical than the overemphasized issue of content exposure or filter bubbles.

    “Such experiments would help understand the interplay between homophily and selective exposure, which may be more critical than the overemphasized issue of content exposure or filter bubbles.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Combining CSS with surveys can address the gap of capturing broader contextual factors, providing both behavioral data and self-reported insights into user motivations and experiences.

    “Combining CSS with surveys can address this gap, providing both behavioral data and self-reported insights into user motivations and experiences.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    The moderate initial agreement could stem from differences in interpretation of the codebook or the inherent complexity of the coding task.

    “This moderate agreement could stem from differences in the interpretation of the codebook or the inherent complexity of the coding task.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Study design and conductreasoning

    This study employed measures such as publishing the codebook, detailing the derivation of code variables, and calculating ICR.

    “This study has aimed to counteract this common issue by employing measures such as publishing the codebook, detailing the derivation of code variables, and calculating ICR.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Randomized experiments, while challenging due to ethical and logistical constraints, are important methods for establishing causality.

    “Randomized experiments, while challenging due to ethical and logistical constraints, are important methods for establishing causality.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    The inter-coder reliability (ICR) falls within a reasonable range, but there is room for improvement.

    “Although the ICR falls within a reasonable range, there is room for improvement.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    CSS methods minimize social desirability bias and measurement error.

    “This approach minimizes social desirability bias and measurement error [75] and is relatively accessible, particularly for European researchers under the upcoming Digital Services Act (DSA).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [75] Barbera, P., Jost, J. T., Nagler, J., Tucker, J. A., & Bonneau, R. (2015). Tweeting from left to right: Is online political communication more than an echo chamber? Psychological Science, 26(10), 1531–1542. https://doi.org/10.1177/0956797615594620 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    The inaccessibility of platform algorithms and their inherent complexity presents significant challenges.

    “The inaccessibility of platform algorithms and their inherent complexity-often requiring live observation to understand their real-world effects-presents significant challenges.”
    Quote in the paperNot a substantial claim
180 of 180
  • The paper relies on this without support.

    Social media and recommendation technologies are sociotechnical systems embedded in a complex, dynamic political and social system that may have multiple feedback loops.

    “We understand social media and recommendation technologies as sociotechnical systems embedded in a complex, dynamic political and social system that may have multiple feedback loops.”
  • The paper relies on this without support.

    The included studies' reported conceptualizations and operationalizations can be reliably categorized into the review's categories.

    “This review contributes to a more nuanced understanding of the echo chamber construct by categorizing and systematically measuring these varying approaches.”
  • The paper relies on this without support.

    The association between methodology and outcomes reflects a causal influence of methodological choices rather than confounding.

    “These interconnections demonstrate how conceptual frameworks and methodological approaches influence the outcomes of echo chamber research.”
  • The paper relies on this without support.

    The corpus of included studies is representative of the broader field of echo chamber research.

    “Our systematic review demonstrates that differing conceptualizations and operationalizations of echo chambers significantly shape research outcomes.”
  • The paper relies on this without support.

    The 129 studies included in the review are representative of the broader literature on echo chambers.

    “We conducted a systematic review of 129 studies investigating the antecedents, characteristics, and effects of echo chambers on social media.”
  • The paper relies on this without support.

    The United States has a two-party political system.

    “highlighting a critical gap in understanding echo chambers within nontwo-party political systems.”
6 of 6

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Platform table lists more surveys than the entire corpus

    Major

    The methods section reports 20 surveys in total, but Table 6 assigns 35 surveys to the SM-Sites category alone.

  • Content-exposure surveys exceed the stated broader-media survey count

    Minor

    The paper says 17 surveys examined general social media use or the whole media diet, but later says 18 content-exposure surveys examined the entire media landscape.

  • Douyin table labels its findings mixed rather than positive

    Minor

    Table 7 reports no positive findings and one mixed finding for Douyin, but the corpus results table labels the Douyin study by Gao et al. as Positive.

  • China study count differs between country tables

    Minor

    Table 4 counts four studies covering China, whereas Table 8 gives China a total of six.

  • Reddit table reports no mixed findings despite a mixed Reddit study

    Minor

    Table 7 records zero mixed findings for Reddit, while the corpus results table labels the Reddit study by Treen et al. as Mixed.

  • TikTok research is described as absent despite a cited included study

    Minor

    The paper says research on TikTok is notably absent, but it earlier describes Gao et al. as having analyzed TikTok.

6 of 6

Cites

Flagged first, then by citations

Research works printed but not linked: 8

  1. Sunstein, C. (2001). Republic.com. Princeton University Press
  2. Habermas, J. (2010). Hat die demokratie noch eine epistemische dimension? Ach EuropaKleine Politische Schriften 11 (pp. 138–191). Suhrkamp Verlag AG.
  3. Arguedas, A. R., Robertson, C., Fletcher, R., & Nielsen, R. K. (2022). Echo chambers, filter bubbles, and polarisation: A literature review. Reuter Institute for the Study of Journalism. Accessed 10 March 2022.
  4. Popay, J., Roberts, H., Sowden, A., Petticrew, M., Arai, L., Rodgers, M., Britten, N., Roen, K., Duffy, S., et al. (2006). Guidance on the conduct of narrative synthesis in systematic reviews. A Product from the ESRC Methods Programme Version, 1(1), 92.
  5. Matuszewski, P. (2019). Selective exposure on polish political and news media facebook pages. Polish Sociological Review, 206, 177–197. https://doi.org/10.26412/psr206.04 · DOI
  6. Powers, E., Koliska, M., & Guha, P. (2019). “Shouting matches and echo chambers”: Perceived identity threats and political self-censorship on social media. International Journal of Communication, 13, 3630–3649.
  7. Bail, C. A., Argyle, L. P., Brown, T. W., Bumpus, J. P., Chen, H., Hunzaker, M. F., Lee, J., Mann, M., Merhout, F., & Volfovsky, A. (2018). Exposure to opposing views on social media can increase political polarization. Proceedings of the National Academy of Sciences, 115(37), 9216–9221. · DOI · Paper page
  8. Gallwitz, F., & Kreil, M. (2021). The rise and fall of ’social bot’ research. SSRN.

Cited by

Sorted by citations

Authors
Hartmann, D., Wang, S. M., Pohlmann, L., & Berendt, B.
Affiliations
  • Weizenbaum Institute (DE)
  • University of Wuppertal (DE)
Corresponding author
Hartmann, David
Venue
Journal of Computational Social Science
Published
2025-04-07
Volume
8
Issue
2
ISSN
  • 2432-2717 (ISSN-L)
  • 2432-2725
OpenAlex
W4409203368
Cited by
59
References
173
Citations by year
2026: 48 · 2025: 11
FWCI
33.23
Type
journal article
Language
en
Open access
Locations
  • Journal of Computational Social Science (publishedVersion, cc-by)
  • RePEc: Research Papers in Economics (submittedVersion)
Funders
  • Bundesministerium für Bildung und Forschung (16DII113f)
  • Weizenbaum-Institut e.V.
Topics
  • Social Sciences › Communication › Social Media and Politics
  • Social Sciences › Sociology and Political Science › Misinformation and Its Impacts
  • Social Sciences › Sociology and Political Science › Media Influence and Politics
Keywords
echo chambers, filter bubbles, conceptualization and operationalization, measurement bias, homophily, algorithmic bias, content exposure, media environment, polarization, fragmentation, instant messaging apps, short video platforms, multiparty system, Digital Services Act, algorithmic auditing, cross-platform comparison

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-11-02.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-11-02.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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