AI summary · arXiv: 2005.11401v1 · cs.CL

Retrieval-Augmented Generation for Knowledge-Intensive NLP Tasks

Patrick Lewis, Ethan Perez, Aleksandara Piktus, Fabio Petroni, Vladimir Karpukhin, Naman Goyal, Heinrich Küttler, Mike Lewis,
and 4 more authorsWen-tau Yih, Tim Rocktäschel, Sebastian Riedel, Douwe Kiela
Original paper Submitted to arXiv on 22 May. 2020 License: NONEXCLUSIVE-DISTRIB 1.0

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The essentials

  • Large pre-trained language models have limitations in accessing and manipulating knowledge
  • Performance of these models is not as good as task-specific architectures on knowledge-intensive tasks
  • The authors propose retrieval-augmented generation (RAG) models that combine pre-trained parametric and non-parametric memory for language generation
  • RAG models use a pre-trained seq2seq model as parametric memory and a dense vector index of Wikipedia accessed through a pre-trained neural retriever as non-parametric memory
  • Two formulations of RAG models are compared: one with the same retrieved passages throughout the generated sequence, and another with different passages per token
  • Fine-tuning and evaluation on various knowledge-intensive NLP tasks show state-of-the-art results on three open domain QA tasks, outperforming parametric seq2seq models and task-specific retrieve and extract architectures
  • RAG models generate more specific, diverse, and factual language compared to a state-of-the-art parametric-only seq2seq baseline for language generation tasks

Key points written by AI: they may contain errors, check them against the paper.

AI-generated keywords: Retrieval-augmented generation Pre-trained language models Knowledge-intensive tasks Parametric memory Non-parametric memory

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The paper discusses the limitations of large pre-trained language models in accessing and manipulating knowledge, particularly on knowledge-intensive tasks. While these models excel in fine-tuning on downstream NLP tasks, their performance falls behind task-specific architectures. To address this issue, the authors propose a solution by introducing retrieval-augmented generation (RAG) models that combine pre-trained parametric and non-parametric memory for language generation. The parametric memory is a pre-trained seq2seq model while the non-parametric memory is a dense vector index of Wikipedia accessed through a pre-trained neural retriever. Two formulations of RAG models are compared: one that conditions on the same retrieved passages throughout the generated sequence and another that allows different passages per token. Fine-tuning and evaluation on various knowledge intensive NLP tasks show state of the art results on three open domain QA tasks outperforming both parametric seq2seq models and task specific retrieve and extract architectures. Additionally, RAG models generate more specific, diverse and factual language compared to a state of the art parametric only seq2seq baseline for language generation tasks. The paper is authored by Patrick Lewis, Ethan Perez, Aleksandara Piktus, Fabio Petroni, Vladimir Karpukhin, Naman Goyal, Heinrich Küttler Mike Lewis Wen tau Yih Tim Rocktäschel Sebastian Riedel and Douwe Kiela.

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Prior work it builds on

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  4. Close Same method, another problem
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  5. Close Groundwork for this paper
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