What's in the Box? A Preliminary Analysis of Undesirable Content in the Common Crawl Corpus

Abstract: Whereas much of the success of the current generation of neural LLMs has been driven by increasingly large training corpora, relatively little research has been dedicated to analyzing these massive sources of textual data. In this exploratory analysis, we delve deeper into the Common Crawl, a colossal web corpus that is extensively used for training LLMs. We find that it contains a significant amount of undesirable content, including hate speech and sexually explicit content, even after filtering procedures. We discuss the potential impacts of this content on LLMs and conclude with future research directions and a more mindful approach to corpus collection and analysis.