Walk me through how you would filter Common Crawl to pr...

A robust filtering pipeline starts with language identification to isolate English text. Next, apply heuristic rules to remove low-quality content. Then, use perplexity filtering with a KenLM model trained on a high-quality reference corpus to score the text. Finally, a fastText or neural quality classifier can be used to further refine the dataset, with expected token retention quantified at each stage.