Claim LD09-SL-C21 (v1.0)

In a formal model of firms hiring from a shared pool, there are conditions under which adopting a shared, more accurate screening algorithm is the dominant choice for both firms in a two-firm model yet lowers overall welfare compared with each firm using its own noisier judgement; under one standard ranking model (Plackett–Luce) the effect disappears.

Provenance and status

Claim type: INTERPRETATION (as printed: “INTERPRETATION”)
Publication status: ELIGIBLE (INTERPRETATION_LABEL) (as printed: “ELIGIBLE WITH INTERPRETATION LABEL”)
Verification state: CONTENT_VERIFIED_PRIMARY (as printed: “CONTENT VERIFIED”; verified by: UNKNOWN)
Does not license: Any estimate of how large the loss is in real markets
Source (field 6, as printed): Kleinberg & Raghavan, “Algorithmic monoculture and social welfare,” PNAS 118, 2021 (arXiv:2101.05853)
Source type (field 7): PEER_REVIEWED_JOURNAL_ARTICLE (as printed: “Peer-reviewed journal article”)
Institutional position: Independent academic
Maturity (claim evidence / publication maturity): CONTESTED (as printed: “CONTESTED”)
Recorded date: 2026-10-15
Currentness / correction: This is the current version. No correction or concern relation is recorded on its Sources.

Version

Current version v1.0, resolved through the explicit current pointer CLAIM--LD09-SL-C21.

Versions:v1.0 · current

Pinned Sources (field 6, version-specific)

“Kleinberg & Raghavan, “Algorithmic monoculture and social welfare,” PNAS 118, 2021 (arXiv:2101.05853)” → SRC-SL-KLEINBERG-RAGHAVAN-PNAS-2021--v1.0 — Kleinberg & Raghavan, “Algorithmic monoculture and social welfare,” PNAS 118, 2021 (arXiv:2101.05853); class PEER_REVIEWED_JOURNAL_ARTICLE (explicit public provenance pin)

All 25 canonical Claim fields (raw values and normalized values)

#	Canonical field	Canonical value (verbatim)	Normalized (Claim Value Vocabulary v1.0.2)
1	CLAIM ID	LD09-SL-C21	—
2	PUBLIC-FACING CLAIM	In a formal model of firms hiring from a shared pool, there are conditions under which adopting a shared, more accurate screening algorithm is the dominant choice for both firms in a two-firm model yet lowers overall welfare compared with each firm using its own noisier judgement; under one standard ranking model (Plackett–Luce) the effect disappears.	—
3	CLAIM TYPE	INTERPRETATION	base_types: INTERPRETATION
4	RESEARCH STRAND	C — Systems, decisions and shared knowledge	—
5	MATURITY	CONTESTED	states: CONTESTED
6	SOURCE	Kleinberg & Raghavan, “Algorithmic monoculture and social welfare,” PNAS 118, 2021 (arXiv:2101.05853)	source_ids: SRC-SL-KLEINBERG-RAGHAVAN-PNAS-2021
7	SOURCE TYPE	Peer-reviewed journal article	classes: PEER_REVIEWED_JOURNAL_ARTICLE
8	INSTITUTIONAL POSITION	Independent academic	—
9	SCOPE	Stylized competitive hiring	—
10	DESIGN	Mathematical model with probabilistic rankings	—
11	SAMPLE / DATASET	Not applicable (theory)	—
12	MODEL / TOOL / VERSION	A shared algorithmic ranking compared with independent human rankings	—
13	COMPARATOR	Each firm using an independent, noisier ranking	—
14	MAIN RESULT	Theorem: for suitable noise models, using the algorithm is a strictly dominant strategy for both firms but social welfare would be higher if both used human evaluators; no effect under Plackett–Luce	—
15	INFERENTIAL TARGET	Whether individually rational adoption of a shared algorithm can be collectively costly	—
16	DOES NOT LICENSE	Any estimate of how large the loss is in real markets	—
17	VERIFICATION STATE	CONTENT VERIFIED	state: CONTENT_VERIFIED_PRIMARY · verified_by: UNKNOWN
18	LIMITATIONS	Read in the arXiv version the authors mark as appearing in PNAS; the result depends on the noise model; the main theorem covers two firms, and settings with more firms are explored computationally	—
19	CONTRADICTORY / SUPPORTING SOURCES	Monoculture defended: LD09-SL-C22	—
20	GEOGRAPHY / LANGUAGE	Not applicable / English	—
21	DISTRIBUTIONAL LEDGER	Applicants screened out by a shared algorithm may be screened out everywhere	—
22	R01 / FIELD-MAP LINKS	LD-09, D3	—
23	WHAT WOULD CHANGE THIS CLAIM?	Empirical estimates of welfare loss in real screening markets	—
24	PUBLICATION STATUS	ELIGIBLE WITH INTERPRETATION LABEL	state: ELIGIBLE · qualifiers: INTERPRETATION_LABEL
25	RECORDED DATE	2026-10-15	—

Field 22 references resolved against Field Map v0.2: LD-09 (LIVING_DEBATE); D3 (DOMAIN)

Cited by Living Debate versions

LD-09 v0.1

Research-of-record provenance

Materialized by sociolens-materializer 0.6.0 at 2026-09-28T20:00:00.000Z; normalization contract SocioLens — Claim Value Vocabulary v1.0.2 — Pre-Spike Materialization Contract (v1.0.2). Content seal SHA-256 3cfa7dbc0243225ecc3d6755cd7c8e834ce81cb45ba07a4fcfb121df431090bc.

Repository-authored inputs (not Drive exports)

SocioLens claim — LD09-SL-C21 v1.0 (v1.0) — written in the SocioLens repository by Project Lead (Claude, AI) on 2026-10-15; no Drive identity exists. Authority: AGENTS.md "Authority" (the Project Lead decides research content within the research-integrity rules) and the Owner's choice in the SocioLens project chat on 15 October 2026 to build the LD-09 debate; a new Claim, first version, written from the project's LD-09 source notes, checked against full texts or official abstracts. Block “ENTRY 21 — LD09-SL-C21” SHA-256 74a23270e57335a7629555713f0222676df68f68e5c39311312ff63ece9368a0; fixture fixtures/authored/claims/LD09-SL-C21--v1.0.

Builder decisions (not Drive data)

VERSION = v1.0 — basis: Claim version taken from the repository-authored claim fixture version (SocioLens claim — LD09-SL-C21 v1.0); the first version of a new Claim of the LD-09 debate
CURRENT_POINTER = true — basis: repository-authored claim "SocioLens claim — LD09-SL-C21 v1.0" (Project Lead (Claude, AI), 2026-10-15); basis: AGENTS.md "Authority" (the Project Lead decides research content within the research-integrity rules) and the Owner's choice in the SocioLens project chat on 15 October 2026 to build the LD-09 debate; a new Claim, first version, written from the project's LD-09 source notes, checked against full texts or official abstracts
FIELD_6_SOURCE_REFERENCE = SRC-SL-KLEINBERG-RAGHAVAN-PNAS-2021--v1.0 — basis: field 6 of ENTRY 21 — LD09-SL-C21 cites "Kleinberg & Raghavan, “Algorithmic monoculture and social welfare,” PNAS 118, 2021 (arXiv:2101.05853)"; the only field-6 segment of this ClaimVersion's repository-authored ledger block.
SOURCE_PROVENANCE_PIN = SRC-SL-KLEINBERG-RAGHAVAN-PNAS-2021--v1.0 — basis: explicit version-pinned public provenance of this ClaimVersion (Amendment v1.2 §6): the pinned field-6 Source record "Kleinberg & Raghavan, “Algorithmic monoculture and social welfare,” PNAS 118, 2021 (arXiv:2101.05853)".