---
title: "Retrieve and Refine — Weston 2018"
description: "Neural generators for open-domain chat often give bland, short replies built from common words."
authors: ["Jason Weston", "Emily Dinan", "Alexander Miller"]
year: 2018
venue: "Proceedings of the 2018 EMNLP Workshop SCAI: The 2nd International Workshop on Search-Oriented Conversational AI"
source: "https://aclanthology.org/W18-5713/"
doi: "10.18653/v1/w18-5713"
arxiv: "1808.04776"
licence: "CC BY 4.0 (ACL Anthology)"
licence_url: "https://creativecommons.org/licenses/by/4.0/"
summary_licence: "Elamur Cosmic License"
canonical: "https://research.elamur.ai/free/en/papers/weston-2018-retrieve-refine-improved-sequence-generation/"
---
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# Retrieve and Refine: Improved Sequence Generation Models For Dialogue

**Authors:** [Jason Weston](https://md.research.elamur.ai/free/en/authors/jason-weston/), [Emily Dinan](https://md.research.elamur.ai/free/en/authors/emily-dinan/), [Alexander Miller](https://md.research.elamur.ai/free/en/authors/alexander-miller/) · **Year:** 2018 · **Venue:** Proceedings of the 2018 EMNLP Workshop SCAI: The 2nd International Workshop on Search-Oriented Conversational AI · **Licence:** [CC BY 4.0 (ACL Anthology)](https://creativecommons.org/licenses/by/4.0/)

**Links:** [Publisher's page](https://aclanthology.org/W18-5713/) · [PDF](https://aclanthology.org/W18-5713.pdf) · [DOI 10.18653/v1/w18-5713](https://doi.org/10.18653/v1/w18-5713) · [arXiv 1808.04776](https://arxiv.org/abs/1808.04776) · [OpenAlex](https://openalex.org/W2885421725)

**Citations:** 164 citations (openalex-snapshot · 2026-10-14) · [90](#cited-by) in our library, of the 140884 papers whose bibliographies we read

## Summary
Neural generators for open-domain chat often give bland, short replies built from common words. Retrieval systems can return livelier responses, but they can only choose from a fixed pool, so their answers may not fit the context. The authors combine the two in RetrieveNRefine (RetNRef). A Key-Value Memory Network retriever picks a candidate utterance, which is appended to the dialogue history. A 2-layer attentive LSTM Seq2Seq model then reads this input and produces the final reply. Two heuristics strengthen the approach. RetNRef+ drops the persona sentences from the generator input, which pushes the generator to rely more on the retrieved candidate. RetNRef++ adds a rule that outputs the retrieved text verbatim whenever the generated reply largely overlaps with it. On the ConvAI2 persona-chat task, perplexity gives little useful signal. Human judges, however, rated RetNRef++ as more engaging than both the Seq2Seq and Memory Network baselines. Its outputs also resembled human utterances more closely in length and rare-word use. The work shows that retrieval can help generative dialogue models produce less generic replies.

## Key points
- **Data:** ConvAI2, a modified and larger version of PersonaChat, with about 160,000 utterances in about 11,000 dialogues. Personas come from a pool of 1155. Implementation uses ParlAI.
- **Training:** For each training turn, the top 100 retrieved candidates are reranked by embedding similarity to the gold reply. The copy rule in RetNRef++ triggers at more than 60% word overlap.
- **Perplexity results:**
  - No retrieval: 31.4.
  - Memory Network retrieval: 31.8.
  - Random retrieval: 32.0.
  - Gold reply's nearest neighbour as the retrieval: 25.9.
  - Gold reply itself: 9.2.
  - The history-truncating variant: 48.4, despite its better human scores.
- **Human evaluation (600 dialogues):**
  - Engagingness was 3.80 for RetNRef++, 3.66 for the Memory Network and 2.70 for Seq2Seq.
  - In A/B tests, RetNRef++ won about 54% of decisive comparisons against each baseline (ties excluded), which was statistically significant.
  - RetNRef++ was weaker at persona use, scoring 0.65 vs 0.90 for Seq2Seq.
- **Output statistics:**
  - Average reply length was 12.7 words for RetNRef++, 11.7 for Seq2Seq and 13.0 for humans.
  - Words with frequency under 1k made up 10.9% of RetNRef++ output, against 11.5% for humans and 5.8% for Seq2Seq.
  - About 53% of RetNRef++ outputs overlap the retrieved text by more than 80%, so it mixes copying with novel generation.

*Our summary of the paper, in our own words — not its text. The work belongs to its authors; read it at the links above.*

Fields: [Natural language processing](https://md.research.elamur.ai/free/en/shelves/nlp/)

## Cited by

Cited by

90 papers of our library cite it (of the 140884 whose bibliographies we read); 9 of them have a page here, 81 not yet.

- [Controllable Paraphrase Generation with a Syntactic Exemplar](https://md.research.elamur.ai/free/en/papers/chen-2019-controllable-paraphrase-generation-syntactic-exemplar/)
- [The Second Conversational Intelligence Challenge (ConvAI2)](https://md.research.elamur.ai/free/en/papers/dinan-2019-second-conversational-intelligence-challenge-convai2/)
- [ConveRT: Efficient and Accurate Conversational Representations from Transformers](https://md.research.elamur.ai/free/en/papers/henderson-2020-convert-efficient-accurate-conversational-representations/)
- [MoEL: Mixture of Empathetic Listeners](https://md.research.elamur.ai/free/en/papers/lin-2019-moel-mixture-empathetic-listeners/)
- [What Makes Good In-Context Examples for GPT-3?](https://md.research.elamur.ai/free/en/papers/liu-2022-what-makes-good-context-examples/)
- [Justifying Recommendations using Distantly-Labeled Reviews and Fine-Grained Aspects](https://md.research.elamur.ai/free/en/papers/ni-2019-justifying-recommendations-distantly-labeled-reviews/)
- [Recipes for Building an Open-Domain Chatbot](https://md.research.elamur.ai/free/en/papers/roller-2021-recipes-building-open-domain-chatbot/)
- [“I'm sorry to hear that”: Finding New Biases in Language Models with a Holistic Descriptor Dataset](https://md.research.elamur.ai/free/en/papers/smith-2022-i-m-sorry-hear-that/)
- [Neural Text Generation with Unlikelihood Training](https://md.research.elamur.ai/free/en/papers/welleck-2019-neural-text-generation-unlikelihood-training/)

## Cite

The paper itself, not this page. BibTeX from the library's record of the work.

```bibtex
@inproceedings{weston2018retrieve,
  title = {{Retrieve and Refine: Improved Sequence Generation Models For Dialogue}},
  author = {Weston, Jason and Dinan, Emily and Miller, Alexander},
  booktitle = {Proceedings of the 2018 EMNLP Workshop SCAI: The 2nd International Workshop on Search-Oriented Conversational AI},
  year = {2018},
  doi = {10.18653/v1/w18-5713},
  eprint = {1808.04776},
  archivePrefix = {arXiv},
  url = {https://doi.org/10.18653/v1/w18-5713}
}
```

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## References

13 references, 3 of them with a card of ours. ↗ leads to the work, «find» searches for one we have no id for yet.

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8. Saizheng Zhang, Emily Dinan, Jack Urbanek, Arthur Szlam, Douwe Kiela, and Jason Weston. 2018. Personalizing dialogue agents: I have a dog, do you have pets too? arXiv preprint arXiv:1801.07243. [find](https://scholar.google.com/scholar?q=Saizheng+Zhang%2C+Emily+Dinan%2C+Jack+Urbanek%2C+Arthur+Szlam%2C+Douwe+Kiela%2C+and+Jason+Weston%2E+2018%2E+Personalizing+dialogue+agents%3A+I+have+a+dog%2C+do+you+have+pets+too%3F+arXiv+preprint+arXiv%3A1801%2E07243%2E) [our card](https://md.research.elamur.ai/free/en/papers/zhang-2018-personalizing-dialogue-agents-i-have/)
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