Papers › Simple Entity-Centric Questions Challenge Dense Retrievers
Simple Entity-Centric Questions Challenge Dense Retrievers
Christopher Sciavolino, Zexuan Zhong, Jinhyuk Lee, Danqi Chen
Open-domain question answering has exploded in popularity recently due to the success of dense retrieval models, which have surpassed sparse models using only a few supervised training examples. However, in this paper, we demonstrate current dense models are not yet the holy grail of retrieval. We first construct EntityQuestions, a set of simple, entity-rich questions based on facts from Wikidata (e.g., "Where was Arve Furset born?"), and observe that dense retrievers drastically underperform sparse methods. We investigate this issue and uncover that dense retrievers can only generalize to common entities unless the question pattern is explicitly observed during training. We discuss two simple solutions towards addressing this critical problem. First, we demonstrate that data augmentation is unable to fix the generalization problem. Second, we argue a more robust passage encoder helps facilitate better question adaptation using specialized question encoders. We hope our work can shed light on the challenges in creating a robust, universal dense retriever that works well across different input distributions.
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Tasks
Datasets
Introduced by this paper, per the archive.
Results from the paper archive 2025-07-28
| Task | Dataset | Model | Metric | Value | Rank at snapshot | Leaderboard | Report |
|---|---|---|---|---|---|---|---|
| Passage Retrieval | EntityQuestions | BM25 | Recall@20 | 0.720 | #3 of 7 | Archive leaderboard | report |
| Passage Retrieval | EntityQuestions | DPR-multi | Recall@20 | 0.567 | #6 of 7 | Archive leaderboard | report |
| Passage Retrieval | EntityQuestions | DPR-NQ | Recall@20 | 0.497 | #7 of 7 | Archive leaderboard | report |
Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.
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