ACL 2022findings29 citations

Why Exposure Bias Matters: An Imitation Learning Perspective of Error Accumulation in Language Generation

Kushal Arora, Layla El Asri, Hareesh Bahuleyan, Jackie Cheung

Abstract

Current language generation models suffer from issues such as repetition, incoherence, and hallucinations. An often-repeated hypothesis for this brittleness of generation models is that it is caused by the training and the generation procedure mismatch, also referred to as exposure bias. In this paper, we verify this hypothesis by analyzing exposure bias from an imitation learning perspective. We show that exposure bias leads to an accumulation of errors during generation, analyze why perplexity fails to capture this accumulation of errors, and empirically show that this accumulation results in poor generation quality.

BibTeX
@inproceedings{arora-etal-2022-exposure,
    title = "Why Exposure Bias Matters: An Imitation Learning Perspective of Error Accumulation in Language Generation",
    author = "Arora, Kushal  and
      El Asri, Layla  and
      Bahuleyan, Hareesh  and
      Cheung, Jackie",
    editor = "Muresan, Smaranda  and
      Nakov, Preslav  and
      Villavicencio, Aline",
    booktitle = "Findings of the Association for Computational Linguistics: ACL 2022",
    month = may,
    year = "2022",
    address = "Dublin, Ireland",
    publisher = "Association for Computational Linguistics",
    url = "https://aclanthology.org/2022.findings-acl.58/",
    doi = "10.18653/v1/2022.findings-acl.58",
    pages = "700--710"
}
Why Exposure Bias Matters: An Imitation Learning Perspective of Error Accumulation in Language Generation · ACL 2022