Multimodal controversy detection, which involves determining whether a given video and its associated comments are controversial, plays a pivotal role in risk management on social video platforms. Existing methods typically provide only classification results, failing to identify what aspects are controversial and why, thereby lacking detailed explanations. To address this limitation, we propose a novel Agent-based Multimodal Controversy Detection architecture, termed AgentMCD. This architecture leverages Large Language Models (LLMs) as generative agents to simulate human behavior and improve explainability. AgentMCD employs a multi-aspect reasoning process, where multiple judges conduct evaluations from diverse perspectives to derive a final decision. Furthermore, a multi-agent simulation process is incorporated, wherein agents act as audiences, offering opinions and engaging in free discussions after watching videos. This hybrid framework enables comprehensive controversy evaluation and significantly enhances explainability. Experiments conducted on the MMCD dataset demonstrate that our proposed architecture outperforms existing LLM-based baselines in both high-resource and low-resource comment scenarios, while maintaining superior explainability.

With the increasing prevalence of online communities, social networks have become pivotal platforms for information propagation. However, this rise is accompanied by issues such as the spread of misinformation and online rumors. Community Level Information Pathway Prediction (CLIPP) is proposed to effectively stop the propagation of harmful information within specific communities. While progress has been made in understanding user-level propagation, there is a significant gap in addressing the CLIPP problem at the community level, particularly with regard to social context interpretation and the cold start problem in niche communities. To bridge this gap, we propose a novel model, named Community-Level Propagation Prediction with LLM enhanced Social Context Interpretation and Community Coldstart (ComPaSC3), which integrates three primary modules. The video enhancement module leverages LLMs to enrich the interpretation of multimedia content by embedding world knowledge. The community portrait building module utilizes LLMs to generate detailed community portraits for community interpretation. To tackle the community cold start problem, the dynamic commLink module links non-popular communities to the popular ones based on their portrait similarity, and dynamically updates their relationship weights. Our experimental results demonstrate that ComPaSC3 significantly improves predictive accuracy in both popular and non-popular scenarios. Particularly in non-popular communities, our approach outperforms existing state-of-the-art methods, achieving improvements of 10.00% - 15.20% in Rec@5 and 7.31% - 12.32% in NDCG@10.

Social video platforms have emerged as significant channels for information dissemination, facilitating lively public discussions that often give rise to controversies. However, existing approaches to controversy detection primarily focus on textual features, which raises three key concerns: it underutilizes the potential of visual information available on social media platforms; it is ineffective when faced with incomplete or absent textual information; and the existing datasets fail to adequately address the need for comprehensive multimodal resources on social media platforms. To address these challenges, we construct a large-scale Multimodal Controversial Dataset (MMCD) in Chinese. Additionally, we propose a novel framework named Multi-view Controversy Detection (MVCD) to effectively model controversies from multiple perspectives. Through extensive experiments using state-of-the-art models on the MMCD, we demonstrate MVCD's effectiveness and potential impact.