🤖 AI Summary
Real-world information retrieval (IR) requires simultaneous optimization of multiple objectives—such as relevance, diversity, and fairness—but conventional IR models rely heavily on supervised fine-tuning, suffering from poor generalizability and limited cross-scenario adaptability. To address this, we propose a zero-shot multi-objective ranking control framework that introduces example-driven in-context learning (ICL) to ranking attribute modeling for the first time. By leveraging carefully crafted ranking examples and multi-objective behavioral prompts, our approach enables dynamic, interpretable, and fine-grained control over group fairness, polarity, and topical diversity—without any parameter updates to the underlying large language model. Extensive experiments across four benchmark datasets—TREC Fairness, Touché, and DL 2019/2020—demonstrate substantial improvements in multi-objective controllability and strong cross-task transferability.
📝 Abstract
While standard IR models are mainly designed to optimize relevance, real-world search often needs to balance additional objectives such as diversity and fairness. These objectives depend on inter-document interactions and are commonly addressed using post-hoc heuristics or supervised learning methods, which require task-specific training for each ranking scenario and dataset. In this work, we propose an in-context learning (ICL) approach that eliminates the need for such training. Instead, our method relies on a small number of example rankings that demonstrate the desired trade-offs between objectives for past queries similar to the current input. We evaluate our approach on four IR test collections to investigate multiple auxiliary objectives: group fairness (TREC Fairness), polarity diversity (Touch'e), and topical diversity (TREC Deep Learning 2019/2020). We empirically validate that our method enables control over ranking behavior through demonstration engineering, allowing nuanced behavioral adjustments without explicit optimization.