DataPrep-Bench Evaluates LLM Training Data Preparation Capabilities

Hao Liang, Qifeng Cai, Yibo Lin, Jianzhuo Du, Qifeng Xia, Sizhe Qiu, Linzhuang Sun, Meiyi Qiang, Zhaoyang Han, Xiaochen Ma, Bohan Zeng, Ruichuan An, Conghui He, Wentao Zhang· July 24, 2026 View original

Summary

DataPrep-Bench is a new benchmark that assesses how well LLMs and agents prepare training data, focusing on both data construction and quality evaluation. It measures downstream training utility across six domains and multiple base models.

This new research introduces DataPrep-Bench, a novel benchmark designed to evaluate the end-to-end capabilities of large language models (LLMs) and AI agents in preparing training data. Unlike previous methods, DataPrep-Bench focuses on two critical aspects: the LLM's ability to construct supervised training data from raw sources and its capacity to evaluate the quality of candidate datasets before actual model training. The benchmark defines "quality" by the data's utility for downstream model training, rather than superficial textual properties. The benchmark operates across six diverse domains and with various base models, providing a unified framework for assessment. For data construction, methods are scored by fine-tuning a base model on their generated outputs. The researchers also present Data-Construction-Skill, an agent that significantly improves upon existing baselines. For data quality evaluation, scoring functions are assessed by their correlation with actual downstream performance, with the new Distributional Alignment Score (DAS) showing strong cross-model correlation across multiple domains. DataPrep-Bench offers a comprehensive and grounded approach to measuring progress in LLM-driven data preparation, highlighting the co-equal importance of both data construction and quality evaluation for effective model development.

Why it matters

Professionals building or fine-tuning LLMs need reliable methods to ensure the quality of their training data. This benchmark provides a standardized way to evaluate data preparation tools and techniques, potentially leading to more robust and performant models.

How to implement this in your domain

  1. 1Evaluate current data preparation workflows against DataPrep-Bench metrics to identify weaknesses.
  2. 2Explore integrating Data-Construction-Skill or similar agentic approaches for automated data generation.
  3. 3Adopt the Distributional Alignment Score (DAS) for pre-training data quality assessment to predict downstream performance.
  4. 4Investigate LLM-driven data preparation tools that align with the benchmark's dual focus on construction and quality.

Who benefits

AI DevelopmentData ScienceSoftware EngineeringResearch & Development

Key takeaways

  • DataPrep-Bench is the first unified benchmark for evaluating LLM training data preparation.
  • It assesses both data construction and data quality evaluation based on downstream training utility.
  • New tools like Data-Construction-Skill and Distributional Alignment Score (DAS) show promising results within the benchmark.
  • The benchmark provides a framework for improving LLM performance through better data practices.

Original post by Hao Liang, Qifeng Cai, Yibo Lin, Jianzhuo Du, Qifeng Xia, Sizhe Qiu, Linzhuang Sun, Meiyi Qiang, Zhaoyang Han, Xiaochen Ma, Bohan Zeng, Ruichuan An, Conghui He, Wentao Zhang

"arXiv:2607.20465v1 Announce Type: new Abstract: The quality of training data fundamentally determines the capabilities of large language models (LLMs), yet no unified benchmark exists to measure how well LLMs, agents, and data-centric workflows actually prepare training data end…"

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Originally posted by Hao Liang, Qifeng Cai, Yibo Lin, Jianzhuo Du, Qifeng Xia, Sizhe Qiu, Linzhuang Sun, Meiyi Qiang, Zhaoyang Han, Xiaochen Ma, Bohan Zeng, Ruichuan An, Conghui He, Wentao Zhang on X · view source

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