Difficulty-Based Preference Data Selection by DPO Implicit Reward Gap

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Qi, Xuan, Xu, Rongwu, Jin, Zhijing
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866911689505505280
author Qi, Xuan
Xu, Rongwu
Jin, Zhijing
author_facet Qi, Xuan
Xu, Rongwu
Jin, Zhijing
contents Aligning large language models (LLMs) with human preferences is a critical challenge in AI research. While methods like Reinforcement Learning from Human Feedback (RLHF) and Direct Preference Optimization (DPO) are widely used, they often rely on large, costly preference datasets. The current work lacks methods for high-quality data selection specifically for preference data. In this work, we introduce a novel difficulty-based data selection strategy for preference datasets, grounded in the DPO implicit reward mechanism. By selecting preference data examples with smaller DPO implicit reward gaps, which are indicative of more challenging cases, we improve data efficiency and model alignment. Our approach consistently outperforms five strong baselines across multiple datasets and alignment tasks, achieving superior performance with only 10\% of the original data. This principled, efficient selection method offers a promising solution for scaling LLM alignment with limited resources.
format Preprint
id arxiv_https___arxiv_org_abs_2508_04149
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Difficulty-Based Preference Data Selection by DPO Implicit Reward Gap
Qi, Xuan
Xu, Rongwu
Jin, Zhijing
Computation and Language
Artificial Intelligence
Machine Learning
Aligning large language models (LLMs) with human preferences is a critical challenge in AI research. While methods like Reinforcement Learning from Human Feedback (RLHF) and Direct Preference Optimization (DPO) are widely used, they often rely on large, costly preference datasets. The current work lacks methods for high-quality data selection specifically for preference data. In this work, we introduce a novel difficulty-based data selection strategy for preference datasets, grounded in the DPO implicit reward mechanism. By selecting preference data examples with smaller DPO implicit reward gaps, which are indicative of more challenging cases, we improve data efficiency and model alignment. Our approach consistently outperforms five strong baselines across multiple datasets and alignment tasks, achieving superior performance with only 10\% of the original data. This principled, efficient selection method offers a promising solution for scaling LLM alignment with limited resources.
title Difficulty-Based Preference Data Selection by DPO Implicit Reward Gap
topic Computation and Language
Artificial Intelligence
Machine Learning
url https://arxiv.org/abs/2508.04149