README.md

FEVER Entity Retrieval Benchmark

Frozen benchmark for evaluating retrieval methods on the BEIR FEVER dataset (5.4M Wikipedia articles, 6,666 test queries). All data is pre-built so you can test a new method without re-running BM25 or dense retrieval.

Files

Core benchmark data (for testing new methods)

File	Size	What it is
beir_pool.json	31 MB	BM25 top-100 candidate pool (k1=1.2, b=0.75). 6,666 queries, each with 100 candidate docids + BM25 scores. Your method re-ranks these 100 docs.
queries.jsonl	31 MB	6,666 test queries ({"_id": "...", "text": "..."} per line)
qrels/test.tsv	210 KB	TREC-style relevance judgments (query-id \t doc-id \t relevance)
query_deltas.csv	2 MB	Per-query NDCG@10 for every Hadith variant (used for significance testing)

Evaluation scripts

File	What it does
fever_benchmark.py	FEVERBenchmark().evaluate(rankings) → {"ndcg@10": float, "recall@100": float}
setup_fever_benchmark.py	Regenerate pool from scratch (downloads BEIR, builds index, runs BM25)
beir_controlled_v3.py	The definitive controlled ablation (6,666 queries, 0 errors)
replay_verification.py	Checksums query_deltas.csv against v3 aggregate results

Analysis scripts

File	What it does
significance_test.py	Paired t-test + randomization test + Cohen's d
export_per_query_v2.py	Exports per-query NDCG to CSV with checkpoint resume
significance_report.md	Full significance report generated from the data

Reference results

File	What it contains
beir_controlled_v3_results.txt	Final aggregate scores (all variants)
benchmark_manifest.md	Frozen configuration: dataset hashes, Pyserini version, BM25 params

Baseline Scores

System	NDCG@10
BM25 (k1=1.2, b=0.75)	0.5214
MiniLM Dense	0.6497
Dense + Muttafaq (best Hadith)	~0.6461

How to test a new method

Quick start (using the frozen pool)

import json
from huggingface_hub import hf_hub_download
from fever_benchmark import FEVERBenchmark

# 1. Download the frozen BM25 pool
pool_path = hf_hub_download("Kim-el/fever-ner", "beir_pool.json")
with open(pool_path) as f:
    pool_data = json.load(f)

pool = pool_data["pool"]  # {qid: [[docid, bm25_score], ...]}
qids = pool_data["qids"]  # [qid1, qid2, ...]

# 2. Re-rank with your method
#    For each query, take the 100 candidate docs and assign your own scores.
my_rankings = {}
for qid in qids:
    candidates = pool[qid]  # [[docid, bm25_score], ...]
    
    # Replace this with YOUR scoring function:
    scored = []
    for docid, bm25_score in candidates:
        your_score = your_model.score(query_text=qid, docid=docid)
        scored.append((docid, your_score))
    
    # Sort descending by your score
    scored.sort(key=lambda x: -x[1])
    my_rankings[qid] = scored

# 3. Evaluate
bench = FEVERBenchmark()
results = bench.evaluate(my_rankings)
print(f"NDCG@10: {results['ndcg@10']:.4f}")   # Beat 0.6497?
print(f"Recall@100: {results['recall@100']:.4f}")

If you need query text or relevance judgments

# Download query text
queries_path = hf_hub_download("Kim-el/fever-ner", "queries.jsonl")
with open(queries_path) as f:
    queries = {json.loads(line)["_id"]: json.loads(line)["text"]
               for line in f}

# Download qrels
qrels_path = hf_hub_download("Kim-el/fever-ner", "qrels/test.tsv")
# TREC format: query-id \t doc-id \t relevance

# Get query text for a specific qid
query_text = queries[qid]

# Get ground truth for a specific qid
# (automatically loaded by FEVERBenchmark.evaluate())

Using the evaluation class directly

# The evaluate() method handles qrels loading and NDCG computation.
# Your input:  {qid: [(docid, score), ...]}  — sorted descending by score.
# Output:      {"ndcg@10": float, "recall@100": float, "queries_evaluated": int}

Comparing against baselines

bench.verify_reproduction({
    "BM25 (k1=1.2, b=0.75)": 0.5214,
    "MiniLM Dense": 0.6497,
    "Your Method": results["ndcg@10"],
})

Reproducibility

To reproduce the exact BM25 pool from scratch:

pip install pyserini==0.14.0
python setup_fever_benchmark.py

This downloads BEIR FEVER (3.3 GB), builds the Pyserini Lucene index (6 min), and runs BM25 retrieval (7 min). Expected BM25 NDCG@10: 0.5214 ± 0.001.

Key Research Findings

From the controlled ablation (6,666 queries, 0 errors):

1. MiniLM Dense improves BM25 by +24.6% relative (+0.1283 NDCG@10)
2. Hadith graph signals provide no benefit on top of dense retrieval — all variants were statistically significant but negative (Cohen's d < 0.2)
3. 95.9% of queries are unchanged by Hadith signals; when they fire, they hurt 2:1
4. The conditional benefit of Hadith on weak lexical systems (+4-5% on FTS5 BM25) does NOT generalize to strong dense retrieval

Requirements

• Python 3.8+
• pyserini>=0.14.0 (only needed for pool regeneration)
• Java 11+ (for Pyserini/Lucene)
• huggingface_hub (for downloading)

License

Same as BEIR FEVER — research use.