Stance detection aims to identify the attitude expressed in text towards a specific target. Recent studies on zero-shot and few-shot stance detection focus primarily on learning generalized representations from explicit targets. However, these methods often neglect implicit yet semantically important targets and fail to adaptively adjust the relative contributions of text and target in light of contextual dependencies. To overcome these limitations, we propose a novel two-stage framework: First, a data augmentation framework named Hierarchical Collaborative Target Augmentation (HCTA) employs Large Language Models (LLMs) to identify and annotate implicit targets via Chain-of-Thought (CoT) prompting and multi-LLM voting, significantly enriching training data with latent semantic relations. Second, we introduce DyMCA, a Dynamic Multi-level Context-aware Attention Network, integrating a joint text-target encoding and a content-aware mechanism to dynamically adjust text-target contributions based on context. Experiments on the benchmark dataset demonstrate that our approach achieves state-of-the-art results, confirming the effectiveness of implicit target augmentation and fine-grained contextual modeling.

“研究突发公共卫生事件国际舆情演变规律,对国际舆情资源进行应急管理和舆论疏导有重要借鉴价值。本文使用谷歌新闻数据库以各国针对COVID-19的报道为对象,构建国际舆情数据集。采用主题模型、图神经网络模型,结合时间、空间维度与舆情生命周期探究全球舆论主题-情感的演化态势,模型准确率为0.7973,F1值为0.7826,性能优于其他基线模型。研究发现,各国舆情呈现放射传播状态。国际媒体舆论的情感倾向和讨论主题存在正相关且随时间进行转变。”