{"id":2242,"date":"2026-09-16T13:35:14","date_gmt":"2026-09-16T11:35:14","guid":{"rendered":"https:\/\/www.ideas.edu.pl\/?post_type=publikacje&#038;p=2242"},"modified":"2026-09-16T13:35:14","modified_gmt":"2026-09-16T11:35:14","slug":"is-a-document-educational-or-just-wikipedia-style-pitfalls-of-classifier-based-quality-filtering","status":"publish","type":"publikacje","link":"https:\/\/www.ideas.edu.pl\/en\/publikacje\/is-a-document-educational-or-just-wikipedia-style-pitfalls-of-classifier-based-quality-filtering\/","title":{"rendered":"Is a Document Educational or Just Wikipedia-Style? \u2014 Pitfalls of Classifier-Based Quality Filtering"},"content":{"rendered":"<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Classifier-based Quality Filtering has recently emerged as a fundamental technique in constructing pre-training corpora. The ability to deploy a single model that can replace or supplement a set of heuristics has proven effective across numerous Large Language Models. In this work, we expose a critical vulnerability in this approach by demonstrating how a straightforward Wikipedia-style reformatting operation can substantially alter a model\u2019s quality assessment and enable low-quality content to surpass filtering thresholds. Our analysis reveals that the FineWeb-Edu CQF model would reverse its filtering decision for approximately 7% of evaluated documents, thereby admitting content into the pre-training corpus that would otherwise have been excluded.<\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Autorzy: Mateusz Klimaszewski, Piotr Andruszkiewicz<\/p>\n\n\n\n<div style=\"height:64px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-group is-layout-grid wp-container-core-group-is-layout-5ab56a3c wp-block-group-is-layout-grid\"><\/div>\n\n\n\n<div class=\"wp-block-group is-layout-grid wp-container-core-group-is-layout-5ab56a3c wp-block-group-is-layout-grid\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>","protected":false},"template":"","nazwa-konferencji":[28],"rodzaj-publikacji":[13],"rok-publikacji":[27],"class_list":["post-2242","publikacje","type-publikacje","status-publish","hentry","nazwa-konferencji-konferencja-acl","rodzaj-publikacji-artykul-konferencyjny","rok-publikacji-27"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Is a Document Educational or Just Wikipedia-Style? \u2014 Pitfalls of Classifier-Based Quality Filtering &#8226; IDEAS Instytut Badawczy<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.ideas.edu.pl\/en\/publikacje\/is-a-document-educational-or-just-wikipedia-style-pitfalls-of-classifier-based-quality-filtering\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Is a Document Educational or Just Wikipedia-Style? \u2014 Pitfalls of Classifier-Based Quality Filtering &#8226; IDEAS Instytut Badawczy\" \/>\n<meta property=\"og:description\" content=\"Classifier-based Quality Filtering has recently emerged as a fundamental technique in constructing pre-training corpora. 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