Datasets:

Hyukkyu
/

beir-nfcorpus

pretty_name: BEIR · NFCorpus
license: cc-by-sa-4.0
language:
  - en
multilinguality:
  - monolingual
task_categories:
  - text-retrieval
task_ids:
  - document-retrieval
tags:
  - beir
  - mteb
  - retrieval
  - biomedical
configs:
  - config_name: corpus
    data_files:
      - split: test
        path: corpus/test-*.parquet
  - config_name: qrels
    data_files:
      - split: test
        path: qrels/test-*.parquet
      - split: train
        path: qrels/train-*.parquet
      - split: dev
        path: qrels/dev-*.parquet
  - config_name: queries
    data_files:
      - split: test
        path: queries/test-*.parquet
      - split: train
        path: queries/train-*.parquet
      - split: dev
        path: queries/dev-*.parquet

NFCorpus — BEIR, unified schema

A normalised copy of the dataset behind the mteb task NFCorpus, one of the tasks of the BEIR benchmark as mteb defines it. Same queries, documents and relevance judgements as the benchmark evaluates — reshaped into one strict schema shared by every dataset in this collection.


Source	`mteb/nfcorpus` @ `ec0fa4fe99da` (the revision pinned in `mteb`)
Domain · languages	biomedical · eng
Queries / documents / qrels (all splits)	3,237 / 3,633 / 134,294
Qrels per query	min 1 · mean 38.186 · max 475
Score values	1 ×11,758, 2 ×576
Layout	`queries` · `corpus` · `qrels`, split `test`; `queries`/`qrels` also carry `train`, `dev` — one shared corpus
Splits	`qrels`: train, dev, test · `queries`: train, dev, test
License	`cc-by-sa-4.0`

Schema

config	columns	rules
`queries`	`id: string`, `text: string`	ids unique and non-empty; every query has ≥ 1 qrel
`corpus`	`id: string`, `title: string`, `text: string`	`title` is always present (`""` when the source has none)
`qrels`	`query-id: string`, `corpus-id: string`, `score: int32`	referential integrity to both tables; no duplicate pairs; no floats

Files are Parquet, sorted by id, zstd-compressed, sharded at 500 MB. Every rule above is enforced by a validator before publishing; provenance.json records the source file hashes, what changed, and the output file hashes.

What changed from the source

dev: dropped 2,913 queries that have no qrels in this split (mteb does the same at load time)
test: dropped 2,914 queries that have no qrels in this split (mteb does the same at load time)
train: dropped 647 queries that have no qrels in this split (mteb does the same at load time)
cast qrels.score double -> int32
kept 40 documents whose text is identical to another document's — a property of the source; note that models embed such documents identically and retrieval ties among them are broken by corpus order
renamed _id → id
renamed source splits (queries←queries/queries, corpus←corpus/corpus) to test

Load it

from datasets import load_dataset
queries = load_dataset("Hyukkyu/beir-nfcorpus", "queries", split="test")
corpus  = load_dataset("Hyukkyu/beir-nfcorpus", "corpus", split="test")
qrels   = load_dataset("Hyukkyu/beir-nfcorpus", "qrels", split="test")

Cross-check against the previous layout

This repo previously held the same dataset in BEIR's raw two-repo form (Hyukkyu/beir-nfcorpus + Hyukkyu/beir-nfcorpus-qrels; that layout is kept under the git tag legacy-layout). Before replacing it, the build was compared against it: corpus id set identical (3,633 documents); qrels rows per split test 12,334 = 12,334, train 110,575 = 110,575, dev 11,385 = 11,385.

License and attribution

The data is redistributed under the source's terms — cc-by-sa-4.0. All credit belongs to the original authors; see the source repository and the references in mteb's task metadata (https://www.cl.uni-heidelberg.de/statnlpgroup/nfcorpus/). This repository is an independent repackaging and is not affiliated with the RTEB or MTEB maintainers.

License discrepancy. The upstream dataset card declares cc-by-sa-4.0 while mteb's TaskMetadata declares not specified. This card carries the upstream value as the more conservative choice.