Papers › Phrase-Indexed Question Answering: A New Challenge for Scalable Document Comprehension

Phrase-Indexed Question Answering: A New Challenge for Scalable Document Comprehension

20 Apr 2018EMNLP 2018 10arXiv:1804.07726archive 2025-07-28

Minjoon Seo, Tom Kwiatkowski, Ankur P. Parikh, Ali Farhadi, Hannaneh Hajishirzi

We formalize a new modular variant of current question answering tasks by enforcing complete independence of the document encoder from the question encoder. This formulation addresses a key challenge in machine comprehension by requiring a standalone representation of the document discourse. It additionally leads to a significant scalability advantage since the encoding of the answer candidate phrases in the document can be pre-computed and indexed offline for efficient retrieval. We experiment with baseline models for the new task, which achieve a reasonable accuracy but significantly underperform unconstrained QA models. We invite the QA research community to engage in Phrase-Indexed Question Answering (PIQA, pika) for closing the gap. The leaderboard is at: nlp.cs.washington.edu/piqa

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exact_match_score uwnlp/piqa/squad/piqa_evaluate.py official repository ran · violated contract fingerprinted Apache-2.0 (permissive) · f6c275d6a18330a9 · report
f1_score uwnlp/piqa/squad/piqa_evaluate.py official repository ran · honoured contract fingerprinted Apache-2.0 (permissive) · 2112c433b9c6d343 · report
normalize_answer uwnlp/piqa/squad/piqa_evaluate.py official repository ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · c6a80c065d2e4851 · report
get_predictions uwnlp/piqa/squad/merge.py official repository unverified Apache-2.0 (permissive) · a8bf629888312cc4 · report
get_q2c uwnlp/piqa/squad/merge.py official repository unverified Apache-2.0 (permissive) · 64b18798c8f48ad9 · report

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Question AnsweringReading ComprehensionRetrieval

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