Quality at a Glance: An Audit of Web-Crawled Multilingual Datasets
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Abstract (arXiv)
With the success of large-scale pre-training and multilingual modeling in Natural Language Processing (NLP), recent years have seen a proliferation of large, web-mined text datasets covering hundreds of languages. We manually audit the quality of 205 language-specific corpora released with five major public datasets (CCAligned, ParaCrawl, WikiMatrix, OSCAR, mC4). Lower-resource corpora have systematic issues: At least 15 corpora have no usable text, and a significant fraction contains less than 50% sentences of acceptable quality. In addition, many are mislabeled or use nonstandard/ambiguous language codes. We demonstrate that these issues are easy to detect even for non-proficient speakers, and supplement the human audit with automatic analyses. Finally, we recommend techniques to evaluate and improve multilingual corpora and discuss potential risks that come with low-quality data releases.
Key facts. Cited by 241 papers in the map (data through 7 Oct 2026). Builds on 39 of its 75 references that are in the map. First posted on arXiv 22 Mar 2021.
Builds on
39 of 75 references.
References · 39
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