ParlIR

ParlIR is a test collection built from European Parliament written questions (parliamentary terms 8–10, July 2014 – October 2026) and the official answers of the Commission, the High Representative and the Council. Relevance comes from the institutions' own links: each question is linked to its reply, and replies cite earlier answers. The qrels come from these records, and a sample of the referral citations was checked by a human.

• Paper: ParlIR: A Test Collection for Answer and Precedent Retrieval from European Parliament Written Questions (Marek Šuppa and Viktória Ondrejová, under review)
• Code, pipeline, tutorial and datasheet: https://github.com/NaiveNeuron/ParlIR-ecir-2027

Tasks

Task	Query	Relevant documents	Metric
AnswerRet (answer)	a question	its official reply, among all 76,536 answers	MRR@10
PrecedentRet (precedent)	a new question	the earlier answers its reply cites, among answers published before the question	R@10, R@100
CiteRet (cite)	a question	the same citations, among answers published before the reply	R@10, R@100

precedenthc and citehc keep only referral citations ("…refers the Honourable Member to its answer to…"). answerlenient also accepts answers that are equivalent to the official one (equivalents.jsonl). Splits are by question date: train 2014–2021, dev 2022–2023, test 2024–2026.

Versions

Pin downloads to the revision id below. Each tag is an annotated git tag: the first id is the tag object, which resolves as a revision, and the second is the commit it points to in the history. The paper cites the v1.0 tag id (2176502d8ed7) as the frozen snapshot and the other two versions by tag name.

Tag	Contents	Revision (tag id)	Commit
v1.0	data and qrels (v1.0/)	2176502d8ed76885c17fc85604be33d2cf429368	574ebbdc6c66 (20 Oct 2026)
v1.0-textonly	text-only evaluation export (v1.0/textonly/)	925a8807a3b471beac0dc376826b2e0a086b0bc4	b7745dbd9b1b (22 Oct 2026)
v1.0-evidence-r5	all runs, per-query metrics, audit records, fine-tuned weights (v1.0/experiments/, about 21 GB)	6b381010ef7b07927b30bd4c35bbb1d416f68baf	ddf8c71259e1 (22 Oct 2026)

The evidence supplement was released in five versions between 20 and 22 October 2026 as analyses were added, and -r5 is the final version. The superseded tags (v1.0-evidence, -r2 to -r4) were removed on 3 November 2026. Their commits are still in the history, and the data tag v1.0 was never moved.

from datasets import load_dataset
corpus = load_dataset("NaiveNeuron/parlir", "corpus", revision="2176502d8ed76885c17fc85604be33d2cf429368")

Files (v1.0/)

• corpus.jsonl: _id (<QID>-ASW), text (masked, use this), raw_text (unmasked), date, institution, answers, header, source_url
• queries.jsonl: _id, subject, text (masked, use this), raw_text, date, source_url, type (E/P), term, addressee, author, orig_lang, orig_lang_src, answer, header, split, joint_size
• queries_xling.jsonl: the official non-English versions of questions (7,683 texts, 22 languages)
• equivalents.jsonl: equivalent answers per query (twin_question, duplicate_answer, near_duplicate_answer)
• precedent_meta.jsonl: citation edges per query, with their source (hyperlink, url, text) and a referral flag
• qrels/<task>_<split>.tsv: TREC qrels (qid 0 docid rel), and qrels_jsonl/ with the same qrels as JSONL
• build_manifest.json: counts and SHA-256 checksums

Rules for systems

Systems may use only the text fields. Do not use ids, dates, header, subject, raw_text, source_url, answers or the answer field as retrieval features, because some reveal the answer and others give shortcuts. An answer's id is its question's id plus -ASW (matching ids alone scores MRR@10 0.989), and a date window lifts BM25 from 0.547 to 0.760. Dates are used only by the evaluator's as-of filter for the citation tasks. For those tasks, systems may also use the links from earlier eligible answers to the questions they replied to, as the question-matching baselines do.

The text-only export (v1.0-textonly) is the safest choice for evaluation. Corpus and queries carry only a random id and the masked text, the dates sit in evaluator-only files, and the id mapping is a separate download (v1.0/textonly-provenance/). That mapping is public, so do not use it as a retrieval feature. All stored main-experiment runs score the same on the export. It omits the links that question matching needs.

Baselines (test split)

System	AnswerRet MRR@10	PrecedentRet R@10
BM25	0.547	0.534
BGE-M3	0.525	0.585
Qwen3-Embedding-8B (zero-shot)	0.714	0.632
BM25 question matching	n/a	0.712
BGE-M3 question matching	n/a	0.725

PrecedentRet has 301 test queries, so please report confidence intervals. More results, including fusion, re-ranking, fine-tuning and a label audit with LLM judges, are in the paper and the evidence supplement.

Counts (v1.0)

76,536 answers (Commission 70,397, High Representative 4,181, Council 1,892, unknown 66) and 78,309 questions with a split (train 59,612, dev 7,735, test 10,962).

Task	train (queries / pairs)	dev	test
answer	59,612 / 59,612	7,735 / 7,735	10,962 / 10,962
answerlenient	59,612 / 70,463	7,735 / 7,854	10,962 / 11,239
precedent	2,302 / 3,393	252 / 364	301 / 481
precedenthc	1,788 / 2,462	159 / 208	192 / 269
cite	3,767 / 5,592	299 / 441	396 / 634
citehc	2,991 / 4,199	186 / 245	256 / 352

Known issues of v1.0 (rare unmasked identifier spellings, a few odd dates) are listed in the datasheet. v1.0 stays frozen, and fixes go into the next release.

Licence

Source texts: European Parliament Open Data Portal, © European Union, CC BY 4.0. Commission answers are reused under Decision 2011/833/EU (CC BY 4.0 via C(2019) 1655), Council answers under Decision (EU) 2017/1842. The texts were modified (headers removed, identifiers masked). ParlIR annotations: CC BY 4.0. See LICENSE-DATA.md. Questions are signed by MEPs acting as public office-holders. Removal requests can be filed on the code repository's issue tracker. Accepted removals apply to main and the next release, and published, pinned revisions stay unchanged unless the law requires otherwise.

Citation

@misc{suppa2026parlir,
  title  = {{ParlIR}: A Test Collection for Answer and Precedent Retrieval from {European Parliament} Written Questions},
  author = {{\v{S}}uppa, Marek and Ondrejov{\'a}, Vikt{\'o}ria},
  year   = {2026},
  note   = {Dataset: https://huggingface.co/datasets/NaiveNeuron/parlir},
  url    = {https://github.com/NaiveNeuron/ParlIR-ecir-2027}
}