Yijun Shen
2026
Adaptive Zooming via Relevance-Informed Positional Resource Allocation for Training-free LLM Context Extension
Hongbo Zhao | Huibin Wang | Bin Tang | Xianming Hu | Yihong Huang | Yijun Shen | Nuoyi Chen | Ping Li | Kai Zhang
Findings of the Association for Computational Linguistics: ACL 2026
Hongbo Zhao | Huibin Wang | Bin Tang | Xianming Hu | Yihong Huang | Yijun Shen | Nuoyi Chen | Ping Li | Kai Zhang
Findings of the Association for Computational Linguistics: ACL 2026
Large Language Models exhibit degraded performance when extrapolating beyond training context lengths. Existing training-free methods like positional reuse or interpolation can alleviate this issue in an efficient manner. However, these strategies are semantics-agnostic by only considering relative token distances, which could indiscriminately blur semantically relevant and irrelevant tokens alike.To address this, we introduce an adaptive positional zooming method called **Relevance-Informed Positional Resource Allocation (RiPRA)**. RiPRA formulates positional encoding as a constrained resource allocation, in which a fixed positional budget is distributed across tokens in a longer context based on their semantic relevance to the query: relevant tokens get higher positional resolution, while irrelevant tokens (positions) are compressed. By doing this, RiPRA enables a dynamic and nonparametric positional zooming where the positional resolution is adaptively modulated across queries and network layers, effectively improving long-range context modeling and retrieval capacity. Besides, an isotonic smoothing is used to further enforce a global linear ordering relationship to preserve stability and generalization, together with a chunk-based hierarchical approximation to further reduce inference overhead. Extensive experiments across comprehensive benchmarks including LongBench, L-Eval, Passkey Retrieval, and PG19 demonstrate that RiPRA consistently outperforms existing training-free extrapolation methods, showing the value of relevance-conditioned positional encoding for long-context generalization.
2025
Chain-of-Talkers (CoTalk): Fast Human Annotation of Dense Image Captions
Yijun Shen | Delong Chen | Fan Liu | Xingyu Wang | Chuanyi Zhang | Liang Yao | Yuhui Zheng
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Yijun Shen | Delong Chen | Fan Liu | Xingyu Wang | Chuanyi Zhang | Liang Yao | Yuhui Zheng
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
While densely annotated image captions significantly facilitate the learning of robust vision-language alignment, methodologies for systematically optimizing human annotation efforts remain underexplored. We introduce Chain-of-Talkers (CoTalk), an AI-in-the-loop methodology designed to maximize the number of annotated samples and improve their comprehensiveness under fixed budget constraints (e.g., total human annotation time). The framework is built upon two key insights. First, sequential annotation reduces redundant workload compared to conventional parallel annotation, as subsequent annotators only need to annotate the “residual”—the missing visual information that previous annotations have not covered. Second, humans process textual input faster by reading while outputting annotations with much higher throughput via talking; thus a multimodal interface enables optimized efficiency. We evaluate our framework from two aspects: intrinsic evaluations that assess the comprehensiveness of semantic units, obtained by parsing detailed captions into object-attribute trees and analyzing their effective connections; extrinsic evaluation measures the practical usage of the annotated captions in facilitating vision-language alignment. Experiments with eight participants show our Chain-of-Talkers (CoTalk) improves annotation speed (0.42 vs. 0.30 units/sec) and retrieval performance (41.13% vs. 40.52%) over the parallel method.