← Search

Patrick Lewis

17 accepted papers

2025

FLARE: Faithful Logic-Aided Reasoning and Exploration

EMNLP 2025

Modern Question Answering (QA) and Reasoning approaches with Large Language Models (LLMs) commonly use Chain-of-Thought (CoT) prompting but struggle with generating outputs faithful to their intermediate reasoning chains. While neuro-symbolic methods like Faithful CoT (F-CoT) offer higher faithfulne

Cited by 0SourcePDFScholar
2024

From One to Many: Expanding the Scope of Toxicity Mitigation in Language Models

ACL 2024findings

To date, toxicity mitigation in language models has almost entirely been focused on single-language settings. As language models embrace multilingual capabilities, it’s crucial our safety measures keep pace. Recognizing this research gap, our approach expands the scope of conventional toxicity mitig…

2024

SnapKV: LLM Knows What You are Looking for Before Generation

NeurIPS 2024poster

Large Language Models (LLMs) have made remarkable progress in processing extensive contexts, with the Key-Value (KV) cache playing a vital role in enhancing their performance. However, the growth of the KV cache in response to increasing input length poses challenges to memory and time efficiency. T…

2023

Goodtriever: Adaptive Toxicity Mitigation with Retrieval-augmented Models

EMNLP 2023long findings

Considerable effort has been dedicated to mitigating toxicity, but existing methods often require drastic modifications to model parameters or the use of computationally intensive auxiliary models. Furthermore, previous approaches have often neglected the crucial factor of language's evolving nature…

Cited by 0SourcecodeScholar
2023

Mini-Model Adaptation: Efficiently Extending Pretrained Models to New Languages via Aligned Shallow Training

ACL 2023findings

Prior work shows that it is possible to expand pretrained Masked Language Models (MLMs) to new languages by learning a new set of embeddings, while keeping the transformer body frozen. Despite learning a small subset of parameters, this approach is not compute-efficient, as training the new embeddin…

2023

On the Challenges of Using Black-Box APIs for Toxicity Evaluation in Research

EMNLP 2023long main

Perception of toxicity evolves over time and often differs between geographies and cultural backgrounds. Similarly, black-box commercially available APIs for detecting toxicity, such as the Perspective API, are not static, but frequently retrained to address any unattended weaknesses and biases. We…

Cited by 0SourcecodeScholar
2023

PEER: A Collaborative Language Model

ICLR 2023top-25%

Textual content is often the output of a collaborative writing process: We start with an initial draft, ask for suggestions, and repeatedly make changes. Agnostic of this process, today’s language models are trained to generate only the final result. As a consequence, they lack several abilities cru…

Cited by 129SourcePDFScholar
2023

Task-aware Retrieval with Instructions

ACL 2023findings

We study the problem of retrieval with instructions, where users provide explicit descriptions of their intent along with their queries to guide a retrieval system. Our solution is a general-purpose task-aware retrieval system, trained using multi-task instruction tuning and can follow human-written…

2022

A Few More Examples May Be Worth Billions of Parameters

EMNLP 2022finding

We investigate the dynamics of increasing the number of model parameters versus the number of labeled examples across a wide variety of tasks. Our exploration reveals that while scaling parameters consistently yields performance improvements, the contribution of additional examples highly depends on…

2022

Autoregressive Search Engines: Generating Substrings as Document Identifiers

NeurIPS 2022accept

Knowledge-intensive language tasks require NLP systems to both provide the correct answer and retrieve supporting evidence for it in a given corpus. Autoregressive language models are emerging as the de-facto standard for generating answers, with newer and more powerful systems emerging at an astoni…

2022

Challenges in Generalization in Open Domain Question Answering

NAACL 2022findings

Recent work on Open Domain Question Answering has shown that there is a large discrepancy in model performance between novel test questions and those that largely overlap with training questions. However, it is unclear which aspects of novel questions make them challenging. Drawing upon studies on s…

2022

Domain-matched Pre-training Tasks for Dense Retrieval

NAACL 2022findings

Pre-training on larger datasets with ever increasing model size isnow a proven recipe for increased performance across almost all NLP tasks.A notable exception is information retrieval, where additional pre-traininghas so far failed to produce convincing results. We show that, with theright pre-trai…

2022

Salient Phrase Aware Dense Retrieval: Can a Dense Retriever Imitate a Sparse One?

EMNLP 2022finding

Despite their recent popularity and well-known advantages, dense retrievers still lag behind sparse methods such as BM25 in their ability to reliably match salient phrases and rare entities in the query and to generalize to out-of-domain data. It has been argued that this is an inherent limitation o…

2021

Answering Complex Open-Domain Questions with Multi-Hop Dense Retrieval

ICLR 2021poster

We propose a simple and efficient multi-hop dense retrieval approach for answering complex open-domain questions, which achieves state-of-the-art performance on two multi-hop datasets, HotpotQA and multi-evidence FEVER. Contrary to previous work, our method does not require access to any corpus-spec…

2021

KILT: a Benchmark for Knowledge Intensive Language Tasks

NAACL 2021long

Challenging problems such as open-domain question answering, fact checking, slot filling and entity linking require access to large, external knowledge sources. While some models do well on individual tasks, developing general models is difficult as each task might require computationally expensive…

2020

Retrieval-Augmented Generation for Knowledge-Intensive NLP Tasks

NeurIPS 2020poster

Large pre-trained language models have been shown to store factual knowledge in their parameters, and achieve state-of-the-art results when fine-tuned on downstream NLP tasks. However, their ability to access and precisely manipulate knowledge is still limited, and hence on knowledge-intensive tasks…