---
pretty_name: BEIR · NQ
license: cc-by-nc-sa-3.0
language:
- en
multilinguality:
- monolingual
task_categories:
- text-retrieval
task_ids:
- document-retrieval
tags:
- beir
- mteb
- retrieval
- wikipedia
configs:
- config_name: corpus
  data_files:
  - split: test
    path: corpus/test-*.parquet
- config_name: qrels
  data_files:
  - split: test
    path: qrels/test-*.parquet
- config_name: queries
  data_files:
  - split: test
    path: queries/test-*.parquet
---
# NQ — BEIR, unified schema

A normalised copy of the dataset behind the `mteb` task **`NQ`**, one of the tasks of the [BEIR](https://github.com/beir-cellar/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/nq`](https://huggingface.co/datasets/mteb/nq/tree/b774495ed302d8c44a3a7ea25c90dbce03968f31) @ `b774495ed302` (the revision pinned in `mteb`) |
| Domain · languages | wikipedia · eng |
| Queries / documents / qrels | 3,452 / 2,681,468 / 4,201 |
| Qrels per query | min 1 · mean 1.217 · max 4 |
| Score values | 1 ×4,201 |
| Layout | `queries` · `corpus` · `qrels`, split `test` |
| License | `cc-by-nc-sa-3.0` |

## 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

- **byte-preserved** all text — no whitespace, newline, or control-character normalisation
- cast `qrels.score` double -> int32
- kept 36,943 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

```python
from datasets import load_dataset
queries = load_dataset("Hyukkyu/beir-nq", "queries", split="test")
corpus  = load_dataset("Hyukkyu/beir-nq", "corpus", split="test")
qrels   = load_dataset("Hyukkyu/beir-nq", "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-nq` + `Hyukkyu/beir-nq-qrels`; that layout is kept under the git tag `legacy-layout`). Before replacing it, the build was compared against it: corpus id set **identical** (2,681,468 documents); qrels rows per split `test` 4,201 = 4,201.

## License and attribution

The data is redistributed under the source's terms — `cc-by-nc-sa-3.0`. All credit belongs to the
original authors; see the source repository and the references in `mteb`'s task metadata (https://ai.google.com/research/NaturalQuestions/).
This repository is an independent repackaging and is not affiliated with the RTEB or MTEB maintainers.