A library of observed fault forms in knowledge graphs built from documents

Every fault has a form. Every form does one of seven things to the graph.

113 forms observed on real corpora, each with its provenance, the damage it causes, whether code can cancel it, whether a deletion-only repair can restore the truth, and which kind of truth can judge it. A repair that holds on one form of a damage may fail on another form of the same damage: this is the test matrix that says which.

Browse the forms Query the data Read the schema

10Mergetwo real things become one node 14Splitone thing becomes several nodes 17Spurious edgea relation the source never asserted 33Missinga node or relation the source asserts and the graph lacks 17Wrong valuea property, number or date is wrong 9Wrong labelan entity or relation type is wrong 5Anachronisma fact outside its validity interval, or a superseded status kept 8Corpus parameternot a damage: a property of the corpus composition

Form	Damage	Class	Injection	Seen	Deletion repairs it
Corpus volume Volume du corpus	Corpus parameter	Code can abstain on it	PARAMETER	1	no
Distribution of relation types Distribution des types de relation	Corpus parameter	Irreducible: needs meaning	PARAMETER	1	no
Entity typing Typage des entités	Wrong label	Irreducible: needs meaning	DESIGN	1	partial
Schema constraints Contraintes de schéma	Wrong label	Irreducible: needs meaning	CONSTRAINT	0	partial
Fact redundancy across documents Redondance du fait	Corpus parameter	Code can abstain on it	DUPLICATE	1	no
Diversity of document templates Diversité des gabarits	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Variable length and chunking Longueur variable et découpe	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Salience and distractors Saillance et distracteurs	Spurious edge	Irreducible: needs meaning	INSERT	1	yes
Layout furniture (headers, footers) Mise en forme et habillage	Spurious edge	Cancelled by code when the source is XML	FORMAT	1	yes
Multiple spellings of one entity Graphies multiples d'une entité	Split	Code can abstain on it	RENAME	2	no
Pronominal references Reprises pronominales	Merge	Irreducible: needs meaning	RENAME	1	no
Typos and OCR confusions Bruit de frappe et confusions d'OCR	Split	Silent false: code cannot see it from inside	NOISE	1	no
Acronyms and abbreviations Sigles et abréviations	Merge	Silent false: code cannot see it from inside	RENAME	1	no
Registry identifiers Identifiants de registre	Merge	Cancelled by code	ALTER	1	no
Strict homonyms Homonymes stricts	Merge	Irreducible: needs meaning	RENAME	1	no
Name-to-address bridge Pont nom ↔ adresse	Split	Irreducible: needs meaning	RENAME	1	no
One person in two roles Une personne dans deux rôles	Merge	Irreducible: needs meaning	DESIGN	1	no
Entities that change identity Entités qui changent d'identité	Split	Irreducible: needs meaning	RENAME	1	no
Facts spread across documents Faits répartis entre documents	Missing	Irreducible: needs meaning	MOVE	0	no
Degree of assertion of a link Degré d'affirmation du lien	Spurious edge	Irreducible: needs meaning	ALTER	1	yes
Link status: never, or expired Statut du lien : jamais ou révolu	Anachronism	Irreducible: needs meaning	ALTER	1	yes
Confusable relation types Confusabilité des types de relation	Wrong label	Irreducible: needs meaning	RENAME	1	partial
Hard negatives for typing Négatifs durs de typage	Wrong label	Irreducible: needs meaning	INSERT	1	partial
Undated contradiction Contradiction sans date	Wrong value	Irreducible: needs meaning	ALTER	1	no
Relative dates Dates relatives	Wrong value	Code can abstain on it	ALTER	1	no
Density: documents of no interest Densité : documents sans intérêt	Corpus parameter	Silent false: code cannot see it from inside	INSERT	1	no
Exact and near duplicates Doublons exacts et quasi-doublons	Spurious edge	Cancelled by code	DUPLICATE	1	yes
Successive versions of a document Versions successives d'un document	Anachronism	Code can abstain on it	DUPLICATE	1	yes
Cited documents absent from the corpus Documents cités et absents du fonds	Missing	Code can abstain on it	DELETE	1	no
Truncated or unreadable documents Documents tronqués ou illisibles	Missing	Code can abstain on it	DELETE	0	no
Names damaged by scanning Noms abîmés par le scan	Split	Code can abstain on it	NOISE	0	no
Tables with multi-level headers Tableaux à en-têtes multiples	Spurious edge	Cancelled by code when the source is XML	FORMAT	1	yes
Several languages in one corpus Plusieurs langues dans un même fonds	Split	Code can abstain on it	TRANSLATE	1	no
Genuinely scanned pages Vraies pages scannées	Missing	Silent false: code cannot see it from inside	IMAGE	0	no
Incremental ingestion Ingestion incrémentale	Corpus parameter	Cancelled by code	PARAMETER	0	no
Document reduced to its title Document réduit à son titre	Missing	Irreducible: needs meaning	DELETE	1	no
The title carries the fact Le titre porte le fait	Missing	Irreducible: needs meaning	MOVE	1	no
Period typographic conventions Conventions typographiques d'époque	Split	Irreducible: needs meaning	FORMAT	1	no
Temporal span of the corpus Étendue temporelle du fonds	Corpus parameter	Irreducible: needs meaning	PARAMETER	0	no
Multi-column layout Mise en page multi-colonnes	Missing	Cancelled by code when the source is XML	FORMAT	0	no
Bilingual document Document bilingue	Split	Code can abstain on it	TRANSLATE	1	no
The fact is in the figure Le fait est dans la figure	Missing	Irreducible: needs meaning	IMAGE	1	no
Several documents in one file Plusieurs documents dans un fichier	Merge	Cancelled by code when the source is XML	DUPLICATE	1	no
Bibliographic references Références bibliographiques	Spurious edge	Silent false: code cannot see it from inside	MOVE	1	yes
Multiple dates on one document Dates multiples d'un même document	Wrong value	Code can abstain on it	ALTER	1	no
Redundancy between text and table Redondance entre le texte et le tableau	Corpus parameter	Code can abstain on it	DUPLICATE	1	no
Values with quantified uncertainty Valeurs avec incertitude quantifiée	Wrong value	Irreducible: needs meaning	ALTER	1	no
Content quoted from elsewhere Contenu repris d'ailleurs	Spurious edge	Irreducible: needs meaning	INSERT	1	yes
Multiple citation conventions Conventions de citation multiples	Missing	Code can abstain on it	FORMAT	1	no
Anonymised entities Entités anonymisées	Merge	Cancelled by code	RENAME	1	no
Local and ambiguous date formats Formats de date locaux et ambigus	Wrong value	Code can abstain on it	ALTER	1	no
Structured abstract in numbered points Résumé structuré en points numérotés	Missing	Irreducible: needs meaning	FORMAT	1	no
Scientific notation inside names Notation scientifique dans les noms	Merge	Silent false: code cannot see it from inside	NOISE	1	no
Relative quantified relations Relations quantifiées relatives	Wrong value	Irreducible: needs meaning	ALTER	1	no
Equipment and supplier entities Entités de matériel et de fournisseurs	Wrong label	Irreducible: needs meaning	INSERT	1	partial
Landscape-oriented table Tableau en orientation paysage	Missing	Cancelled by code when the source is XML	IMAGE	0	no
The table carries its own definitions Le tableau porte ses propres définitions	Missing	Irreducible: needs meaning	MOVE	1	no
Non-atomic cells Cellules non atomiques	Wrong value	Silent false: code cannot see it from inside	ALTER	1	no
Non-standard decimal separator Séparateur décimal non standard	Wrong value	Irreducible: needs meaning	ALTER	1	no
One compound, several names Un composé, plusieurs noms	Split	Irreducible: needs meaning	RENAME	1	no
Mixed units and conventions Unités et conventions mixtes	Wrong value	Code can abstain on it	ALTER	1	no
Collective entity Entité collective	Merge	Irreducible: needs meaning	RENAME	1	no
Complex attributions and affiliations Attributions et affiliations complexes	Spurious edge	Irreducible: needs meaning	FORMAT	1	yes
Text-to-figure reference by label Renvoi texte ↔ figure par étiquette	Missing	Irreducible: needs meaning	MOVE	1	no
Dense relative chronology Chronologie relative dense	Anachronism	Code can abstain on it	ALTER	1	yes
Drop cap Lettrine	Missing	Cancelled by code when the source is XML	NOISE	0	no
Content added by digitisation Contenu ajouté par la numérisation	Spurious edge	Silent false: code cannot see it from inside	INSERT	1	yes
Editorial metadata Métadonnées éditoriales	Spurious edge	Silent false: code cannot see it from inside	INSERT	1	yes
The study type qualifies all its facts Le type d'étude qualifie tous ses faits	Wrong label	Irreducible: needs meaning	ALTER	1	partial
Methods as entities with a genealogy Les méthodes sont des entités avec généalogie	Split	Silent false: code cannot see it from inside	RENAME	1	no
The three PDF regimes (native, OCR layer, pure image) Les trois régimes de PDF (natif · OCR posé · image pure)	Missing	Code can abstain on it	IMAGE	0	no
Sample size written in words L'effectif est écrit en toutes lettres	Wrong value	Code can abstain on it	ALTER	1	no
Sample size is computed, not stated L'effectif ne se lit nulle part, il se calcule	Missing	Code can abstain on it	MOVE	1	no
Furniture language differs from body language La langue du mobilier n'est pas celle du corps	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Significance marker with two meanings Marqueur de significativité à double sens	Wrong label	Irreducible: needs meaning	ALTER	1	partial
No apparatus at all Absence totale d'appareil	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Abbreviation dot inside a unit Point abréviatif dans l'unité	Wrong value	Code can abstain on it	ALTER	1	no
Signature mark of a gathering Signature de cahier	Missing	Cancelled by code when the source is XML	NOISE	0	no
Several DOIs per document Plusieurs DOI par document	Merge	Cancelled by code	INSERT	1	no
Partial ORCID ORCID partiel	Split	Cancelled by code	ALTER	1	no
Structured abstract Résumé structuré	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Pre-registration identifier Préenregistrement (identifiant de registre)	Wrong label	Cancelled by code	INSERT	1	partial
Forest plot as image Forest plot en image	Wrong value	Irreducible: needs meaning	IMAGE	1	no
Ordinal scale by colour Échelle ordinale par couleur	Wrong value	Silent false: code cannot see it from inside	IMAGE	0	no
Supplementary material cited and absent Matériel supplémentaire cité et absent	Missing	Code can abstain on it	DELETE	1	no
Author declarations Déclarations sur les auteurs	Spurious edge	Cancelled by code	INSERT	1	yes
Licence on page 1 Licence en page 1	Spurious edge	Cancelled by code	INSERT	0	yes
Open peer-review furniture Mobilier de relecture ouverte	Spurious edge	Silent false: code cannot see it from inside	INSERT	1	yes
Crossmark badge (retraction status) Badge Crossmark	Anachronism	Cancelled by code	ALTER	1	yes
Unicode traps in native PDF Pièges Unicode du PDF natif	Split	Cancelled by code	NOISE	1	no
Coloured hyperlinks carrying a type Hyperliens colorés porteurs de type	Wrong label	Cancelled by code when the source is XML	IMAGE	0	partial
Running head with dotted initials Running head à initiales pointées	Split	Code can abstain on it	RENAME	1	no
Access format of the document (PDF, HTML, XML) Le format d'accès au document (PDF · HTML · XML)	Corpus parameter	Cancelled by code	PARAMETER	1	no
Numbered display equation Équation numérotée en display	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Bare-number reference with ambiguous target Renvoi par numéro nu, cible ambiguë	Spurious edge	Silent false: code cannot see it from inside	ALTER	1	yes
Quantifier in a column right of the equation Quantificateur en colonne à droite de l'équation	Wrong value	Irreducible: needs meaning	FORMAT	0	no
Numbered theorem whose body is the claim Théorème numéroté dont le corps est l'affirmation	Missing	Irreducible: needs meaning	MOVE	1	no
Pseudo-code with double numbering Pseudo-code à double numérotation	Missing	Cancelled by code when the source is XML	FORMAT	0	no
Structured object presented as a figure Objet structuré présenté comme figure	Missing	Irreducible: needs meaning	MOVE	1	no
Acronym defined by typography alone Sigle défini par la typographie seule	Split	Silent false: code cannot see it from inside	FORMAT	1	no
Repository cover page prepended to the article Couverture de dépôt ajoutée devant l'article	Spurious edge	Cancelled by code when the source is XML	INSERT	0	yes
Two conflicting paginations Deux paginations en conflit	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Display mathematics inside the abstract Le résumé contient des mathématiques en display	Missing	Cancelled by code when the source is XML	FORMAT	0	no
Clickable zone differs from semantic unit Zone cliquable ≠ unité sémantique	Missing	Cancelled by code when the source is XML	FORMAT	1	no
HTML fragments the text Le format html fragmente le texte	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Page 1 is not representative Page 1 non représentative	Spurious edge	Cancelled by code when the source is XML	INSERT	0	yes
Translated verbatim Verbatim traduit	Wrong value	Silent false: code cannot see it from inside	TRANSLATE	1	no
Columns of different natures Colonnes de natures différentes	Spurious edge	Silent false: code cannot see it from inside	FORMAT	1	yes
Three kinds of number in one string Trois natures de nombre dans une chaîne	Wrong value	Silent false: code cannot see it from inside	ALTER	1	no
Mnemonic superscript that is not a power Exposant mnémonique qui n'est pas une puissance	Wrong value	Silent false: code cannot see it from inside	ALTER	1	no
Citation with internal locator Citation avec localisateur interne	Missing	Cancelled by code when the source is XML	FORMAT	1	no
Editorial status printed in the document Statut éditorial imprimé dans le document	Anachronism	Silent false: code cannot see it from inside	ALTER	1	yes
Multiple abstracts from different registries Résumés multiples de registres différents	Missing	Cancelled by code when the source is XML	DUPLICATE	1	no

What a record says

Seven damages

What a fault does to the graph: merge, split, spurious edge, missing, wrong value, wrong label, anachronism. The 113 difficulties observed in August 2026, however different they look, each produce one of these. Verified line by line.

Four classes

Whether deterministic code cancels the form before it enters the graph, can abstain on it, cannot see it from inside, or whether it needs meaning. Half of what was observed is cancelled by code once; the other half is the real benchmark.

Provenance, not opinion

A form enters with a verbatim excerpt from a named corpus, a date, an observer. Cases come with counter-examples. A refuted form stays, marked refuted. Nothing is deleted.

Why it matters

Graph repair is evaluated against constraints the graph must satisfy, not against what is true. The atlas is half of an answer key: the map of forms by damage, with the kind of truth that can judge each. The other half, the truth itself, is built on it.

Contribute a form by pull request on GitHub: one JSON file, the excerpt, the corpus, the date. A second reader reviews. Cite: Gracia S., Bagnol-Lebon C., Comtet Y. (2026). Fault Atlas. Loxyn SAS, Lyon. Zenodo. doi:10.5281/zenodo.22674547.