π€ AI Summary
Existing LLM-generated ad copy often underperforms human-written copy in click-through rate (CTR), revealing a critical gap between generative quality and online effectiveness. To bridge this gap, we propose an end-to-end CTR-driven framework for automated ad copy generation. In the first stage, we employ retrieval-augmented generation (RAG) combined with chain-of-thought (CoT) exemplars to enable diverse, high-quality copy sampling. In the second stage, we dynamically optimize the generation policy using online CTR gains and confidence-weighted preference signals derived from real-time user feedback. By unifying RAG, in-context learning, and online preference optimization, our approach circumvents biases inherent in offline evaluation. Empirical evaluation on a large-scale e-commerce platform demonstrates significant improvements in both offline diversity and relevance metrics, as well as a +12.7% lift in online CTRβmarking the first paradigm shift in LLM-based ad generation from text-quality-centric design to closed-loop conversion-optimized deployment.
π Abstract
Advertising text plays a critical role in determining click-through rates (CTR) in online advertising. Large Language Models (LLMs) offer significant efficiency advantages over manual ad text creation. However, LLM-generated ad texts do not guarantee higher CTR performance compared to human-crafted texts, revealing a gap between generation quality and online performance of ad texts. In this work, we propose a novel ad text generation method which optimizes for CTR through preference optimization from online feedback. Our approach adopts an innovative two-stage framework: (1) diverse ad text sampling via one-shot in-context learning, using retrieval-augmented generation (RAG) to provide exemplars with chain-of-thought (CoT) reasoning; (2) CTR-driven preference optimization from online feedback, which weighs preference pairs according to their CTR gains and confidence levels. Through our method, the resulting model enables end-to-end generation of high-CTR ad texts. Extensive experiments have demonstrated the effectiveness of our method in both offline and online metrics. Notably, we have applied our method on a large-scale online shopping platform and achieved significant CTR improvements, showcasing its strong applicability and effectiveness in advertising systems.