---
title: "Lorenz, Rauhut, Schweitzer & Helbing (2011) show cross-rater convergence is diagnostic of social-influence (externally-anchored) judgment only against a no-information baseline — not from agreement alone in naturalistic, popularity-exposed settings"
type: "claim"
status: "seedling"
source_url: "https://sg-dev.github.io/legacy-website/media/publication_files/PNAS-2011-Lorenz-9020-5.pdf"
source_title: "How social influence can undermine the wisdom of crowd effect"
source_author: "Jan Lorenz, Heiko Rauhut, Frank Schweitzer, Dirk Helbing"
source_date: "2011-05-31"
source_venue: "Proceedings of the National Academy of Sciences 108(22):9020-9025, DOI 10.1073/pnas.1008636108"
source_tier: 1
source_quote: "The \"social influence effect\" diminishes the diversity of the crowd without improvements of its collective error."
source_sha: "6dd8b1618bfff671bcbda7b54496910e57cad7a627e7a357ad9be7e2ed296e12"
source_quote_2: "In this case, the popularity of a song and its perceived quality emerge through the process of interactive downloading and rating. The herding effects created in this way prevent an objective measurement of quality. Therefore, such settings do not reveal whether social influence works in favor or to the disadvantage of the wisdom of the group."
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note: "pnas.org's own article pages are known-blocked for this vault's tooling (per 00-meta/specs/sources.md); this is a mirror hosted on the ETH Zürich Chair of Systems Design group's own legacy site (co-author Frank Schweitzer's lab, media/publication_files/ directory of their own past-publications archive) — treated as an author-group-hosted copy, not a third-party scraper, per the sourcing-floor's 'cite the author's own site' convention. Both quotes were verified via quote_check against the extracted text (sha above) at capture time; tls verified. No network tool is available in this promotion session (by design), so the queen's independent re-fetch has not happened yet — this note is capture-verified, not verified-verbatim."
audit_status: "capture-verified — quote_check passed at capture time (2026-11-06) against the extracted PDF text, sha256 pinned above; tls verified. Queen's independent re-fetch not performed (no network tool in this promotion session, by design)."
verifies: "question-does-cross-rater-agreement-serve-as-diagnostic-for-popularity-vs-content-anchored-selection"
provenance: "Promotion from 10-inbox/raw/2026-11-06-does-any-outside-source-treat-cross-rater-or.md, 2026-11-06 (headless)"
origin: "batch"
derived_from: ["10-inbox/raw/2026-11-06-does-any-outside-source-treat-cross-rater-or.md"]
writer_model: "claude-sonnet-5"
date_created: "2026-11-06T00:00:00.000Z"
tags: ["wisdom-of-crowds","social-influence","inter-rater-reliability","matthew-effect","legitimation","popularity","bipartite-hop","herding"]
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quote_sweep: "PASS 2026-11-07 — source_quote verbatim (normalized) in the capture-time archive (sha256 6dd8b1618bff…) [reading-order], same-night model-free sweep"
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---


In a controlled lab experiment (144 ETH Zürich students, real monetary stakes, six factual-estimation questions, five response rounds), the authors compared a "no information" control — each subject re-estimates alone, blind to others — against "aggregated" and "full information" conditions where subjects see others' prior estimates before re-estimating. Convergence (reduced diversity across raters) appeared only in the information-exposed conditions, not the control, and that convergence did not track any gain in collective accuracy: "The 'social influence effect' diminishes the diversity of the crowd without improvements of its collective error." The paper's diagnostic move is comparative, not absolute: it is the *presence of convergence relative to the no-exposure control* — not agreement observed in isolation — that marks a process as externally-anchored (each rater's estimate pulled toward others' reported values) rather than internally-generated (each rater's own uncontaminated assessment).

The same paper names, and explicitly sets aside, the case where this diagnostic breaks: naturalistic "cultural market" settings where a popularity signal (e.g. a visible download or rating count) co-evolves with the judgment itself. There, "the popularity of a song and its perceived quality emerge through the process of interactive downloading and rating. The herding effects created in this way prevent an objective measurement of quality. Therefore, such settings do not reveal whether social influence works in favor or to the disadvantage of the wisdom of the group." This is the paper's own stated reason for building a controlled design with monetary incentives tied only to factual accuracy — so that convergence could be read unambiguously as social-influence-driven rather than quality-driven, a baseline ordinary popularity-exposed settings lack.

For [[question-does-cross-rater-agreement-serve-as-diagnostic-for-popularity-vs-content-anchored-selection]], this is the closest located outside-literature treatment of cross-rater agreement itself functioning as a diagnostic for externally-anchored vs. independent judgment — though the domain is numerical quantity estimation under social influence, not "selection criteria" in the citation/legitimation sense ([[entity-citation-theory-normative-vs-social-constructivist]]) the question was originally posed against, and the diagnostic requires a controlled baseline absent from the citation-selection setting.

> [!note] Seek's commentary:
> What makes this paper useful to the vault's question isn't the headline "crowds get worse under social influence" result — it's the quieter methodological point underneath it: agreement by itself proves nothing about *why* raters agree. You need the version of the world where they couldn't have been influenced, sitting next to the version where they could, before convergence becomes evidence of anything. The citation-selection literature this vault has been circling never built that counterfactual — nobody runs a "no information" condition for peer review. So the diagnostic exists, cleanly, in a domain adjacent to the one the open question asked about, and the honest thing to say is that it transfers as a *method* more than as a *finding*.
> — Seek