esCorpius: A Massive Spanish Crawling Corpus

Introduction

In the recent years, Transformer-based models have lead to significant advances in language modelling for natural language processing. However, they require a vast amount of data to be (pre-)trained and there is a lack of corpora in languages other than English. Recently, several initiatives have presented multilingual datasets obtained from automatic web crawling. However, the results in Spanish present important shortcomings, as they are either too small in comparison with other languages, or present a low quality derived from sub-optimal cleaning and deduplication. In this work, we introduce esCorpius, a Spanish crawling corpus obtained from near 1 Pb of Common Crawl data. It is the most extensive corpus in Spanish with this level of quality in the extraction, purification and deduplication of web textual content. Our data curation process involves a novel highly parallel cleaning pipeline and encompasses a series of deduplication mechanisms that together ensure the integrity of both document and paragraph boundaries. Additionally, we maintain both the source web page URL and the WARC shard origin URL in order to complain with EU regulations. esCorpius has been released under CC BY-NC-ND 4.0 license.

Statistics

Corpus	OSCAR 22.01	mC4	CC-100	ParaCrawl v9	esCorpius (ours)
Size (ES)	381.9 GB	1,600.0 GB	53.3 GB	24.0 GB	322.5 GB
Docs (ES)	51M	416M	-	-	104M
Words (ES)	42,829M	433,000M	9,374M	4,374M	50,773M
Lang. identifier	fastText	CLD3	fastText	CLD2	CLD2 + fastText
Elements	Document	Document	Document	Sentence	Document and paragraph
Parsing quality	Medium	Low	Medium	High	High
Cleaning quality	Low	No cleaning	Low	High	High
Deduplication	No	No	No	Bicleaner	dLHF
Language	Multilingual	Multilingual	Multilingual	Multilingual	Spanish
License	CC-BY-4.0	ODC-By-v1.0	Common Crawl	CC0	CC-BY-NC-ND

Citation

Link to the paper: https://www.isca-speech.org/archive/pdfs/iberspeech_2022/gutierrezfandino22_iberspeech.pdf / https://arxiv.org/abs/2206.15147

Cite this work:

@inproceedings{gutierrezfandino22_iberspeech,
  author={Asier Gutiérrez-Fandiño and David Pérez-Fernández and Jordi Armengol-Estapé and David Griol and Zoraida Callejas},
  title={{esCorpius: A Massive Spanish Crawling Corpus}},
  year=2022,
  booktitle={Proc. IberSPEECH 2022},
  pages={126--130},
  doi={10.21437/IberSPEECH.2022-26}
}

Disclaimer

We did not perform any kind of filtering and/or censorship to the corpus. We expect users to do so applying their own methods. We are not liable for any misuse of the corpus.