ModelRefs / Information Extraction — AI Glossary
Information Extraction — AI Glossary
Automatically identifying and structuring specific information (entities, relations, events) from unstructured text. Also called IE or structured extraction.
Overview
LLM-based information extraction: named entity recognition, relation extraction (what connects which entities), event extraction (what happened, who, when, where), and structured data extraction (filling JSON schemas from free text). Surpasses traditional NLP pipelines on few-shot IE with structured output prompting. Used in document processing, compliance, and data enrichment.
Reference details
| Topic | applications |
|---|---|
| Also known as | IE, structured extraction |
| Last reviewed | 2026-06-24 |
Related terms
Example: The field that is not in the document
Extract vendor, invoice number, total and purchase-order number into a JSON schema. Three are printed on the page; this particular invoice has no PO number. A model given a required string field will very often produce a plausible one rather than fail. Make the field nullable, instruct explicit abstention, and — the step teams skip — include documents with genuinely missing fields in the evaluation set, scoring “correctly returned null” as its own outcome. Otherwise accuracy is measured only on fields that were present, which is the easy half of the task.
Commonly confused with
Information extraction is the task; structured output is the mechanism. Schema enforcement guarantees the shape of the JSON, never the truth of its contents — a syntactically perfect object can be entirely invented. Grammar-constrained decoding removes parse errors from your problem list and does not touch accuracy.
When to use it
Reach for it when:
- Heterogeneous documents, where a rules-based parser breaks on every new layout
- Few-shot settings with no labelled training data for a dedicated model
- Where downstream systems need typed fields rather than prose
Reach for something else when:
- One stable, high-volume format — a deterministic parser is cheaper and auditable
- Without an abstention path, where a missing field becomes a fabricated one
- Where extracted values feed irreversible actions with no verification step
Continue your research
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Frequently asked questions
What is Information Extraction?
Automatically identifying and structuring specific information (entities, relations, events) from unstructured text.
Is Information Extraction the same as IE?
Yes — IE, structured extraction are common aliases for Information Extraction.
What concepts are related to Information Extraction?
Closely related concepts include named entity recognition, document processing, text classification.