WWW2026

Generative Data Transformation: From Mixed to Unified Data

Jiaqing Zhang, Mingjia Yin, Hao Wang, Yuxin Tian, Yuyang Ye, Yawen Li, Wei Guo, Yong Liu, Enhong Chen

Abstract

Recommendation model performance is intrinsically tied to the quality, volume, and relevance of their training data. To address common challenges like data sparsity and cold start, recent researchs have leveraged data from multiple auxiliary domains to enrich information within the target domain. However, inherent domain gaps can degrade the quality of mixed-domain data, leading to negative transfer and diminished model performance. Existing prevailing model-centric paradigm -which relies on complex, customized architectures -struggles to capture the subtle, non-structural sequence dependencies across domains, leading to poor generalization and high demands on computational resources. To address these shortcomings, we propose Taesar, a data-centric framework for target-aligned sequential regeneration, which employs a contrastive decoding mechanism to adaptively encode cross-domain context into target-domain sequences. It employs contrastive decoding to encode cross-domain context into target sequences, enabling standard models to learn intricate dependencies without complex fusion architectures. Experiments show Taesar outperforms model-centric solutions and generalizes to various sequential models. By generating enriched datasets, Taesar effectively combines the strengths of data-and modelcentric paradigms. The code accompanying this paper is available at https://github.com/USTC-StarTeam/Taesar . CCS Concepts • Information systems → Recommender systems.