Event Argument Extraction (EAE) aims to identify arguments and assign them to predefined roles within a document. Existing methods face challenges in modeling intra-class variance and inter-class ambiguity, hindering accurate role assignment. Inspired by how humans dynamically adjust classification criteria while maintaining category consistency (e.g., distinguishing ''Victim'' and ''Attacker'' roles based on contextual relationships), we propose a HDMAR (Hyperspherical Dynamic Multi-Prototype with Arguments Dependencies and Role Consistency) method, where three innovations tackle these challenges: (1) Hyperspherical dynamic multi-prototype learning is used to capture intra-role diversity and enforce inter-role separation via hyperspherical optimization and optimal transport, (2) cross-event role consistency is used to align role representations across events, and (3) an arguments dependencies-guided encoding module enhances contextual understanding of intra-event and inter-event dependencies. Experiments on RAMS and WikiEvents demonstrate gains in accuracy, with further analysis validating the contributions of each module.

Current research shows that providing instructions to guide Large Language Models (LLMs) improves reasoning tasks, but existing methods struggle to balance accuracy and generalization. Manually crafted instructions tailored to specific LLMs and tasks improve performance but reduce generalizability, while more general instructions lack detail and lower performance. To address this, we propose a dynamic instruction-generation method using an Instruction-Generation Prompt (IGP). IGP categorizes problems into domains and integrates the model's capabilities to generate detailed task-specific instructions, resulting in a comprehensive plan. This approach achieves high precision with general prompts without requiring in-depth knowledge of LLMs or tasks. We validated our method across five LLMs and ten datasets in three task categories. Our dynamically generated instructions outperformed traditionally handcrafted, LLM-specific instructions across various LLMs and tasks.

The long-tailed distribution, also called the heavy-tailed distribution, is common in nature. Since both words and their senses in natural language have long-tailed phenomenon in usage frequency, the Word Sense Disambiguation (WSD) task faces serious data imbalance. The existing learning strategies or data augmentation methods are difficult to deal with the lack of training samples caused by the single application scenario of long-tail senses, and the word sense representations caused by unique word sense definitions. Considering that the features extracted from the Disentangled Representation (DR) independently describe the essential properties of things, and DR does not require deep feature extraction and fusion processes, it alleviates the dependence of the representation learning on the training samples. We propose a novel DR by constraining the covariance matrix of a multivariate Gaussian distribution, which can enhance the strength of independence among features compared to β-VAE. The WSD model implemented by the reinforced DR outperforms the baselines on the English all-words WSD evaluation framework, the constructed long-tail word sense datasets, and the latest cross-lingual datasets.

Social summarization aims to produce a concise summary that describes the core content of a collection of posts on a specific topic. Existing methods tend to produce sparse or ambiguous representations of posts due to only using short and informal text content. Latest researches use social relations to improve diversity of summaries, yet they model social relations as a regularization item, which has poor flexibility and generalization. Those methods could not embody the deep semantic and social interactions among posts, making summaries still suffer from redundancy. We propose to use Social Context and Multi-Granularity Relations (SCMGR) to improve unsupervised social summarization. It learns more informative representations of posts considering both text semantics and social structure information without any annotated data. First, we design two sociologically motivated meta-paths to construct a social context graph among posts, and adopt a graph convolutional network to aggregate social context information from neighbors. Second, we design a multi-granularity relation decoder to capture the deeper semantic and social interactions from post-word and post-post aspects respectively, which can provide guidance for summary selection from semantic and social structure perspectives. Finally, a sparse reconstruction-based extractor is used to select posts that can best reconstruct original content and social network structure as summaries. Our approach improves the coverage and diversity of summaries. Experimental results on both English and Chinese corpora prove the effectiveness of our model.

Social influence is essential to social recommendation. Current influence-based social recommendation focuses on the explicit influence on observed social links. However, in real cases, implicit social influence can also impact users' preference in an unobserved way. In this work, we concern two kinds of implicit influence: Local Implicit Influence of persons on unobserved interpersonal relations, and Global Implicit Influence of items broadcasted to users. We improve the state-of-the-art GNN-based social recommendation methods by modeling two kinds of implicit influences separately. Local implicit influence is involved by predicting unobserved social relationships. Global implicit influence is involved by defining global popularity of each item and personalize the impact of the popularity on each user. In a GCN network, explicit and implicit influence are integrated to learn the social embedding of users and items in social recommendation. Experimental results on Yelp initially demonstrate the effectiveness of proposed model.

Topic detection in social media is a challenging task due to large-scale short, noisy and informal nature of messages. Most existing methods only consider textual content or simultaneously model the posts and the first-order structural characteristics of social networks. They ignore the impact of larger neighborhoods in microblog conversations on topics. Moreover, the simple combination of separated content and structure representations fails to capture their nonlinear correlation and different importance in topic inference. To this end, we propose a novel random walk based Parallel Social Contexts Fusion Topic Model (PCFTM) for weibo conversations. Firstly, a user-level conversation network with content information is built by the reposting and commenting relationships among users. Through random walks of different lengths on network, we obtain the user sequences containing the parallel content and structure contexts, which are used to acquire the flexible-order proximity of users. Then we propose a self-fusion network embedding to capture the nonlinear correlation between parallel social contexts. It is achieved by taking the content embedding sequence processed by CNN as the initial value of structure embedding sequence fed to Bi-LSTM. Meanwhile, a user-level self-attention is further used to mine the different importance of users to topics. Lastly, the user sequence embedding is incorporated into neural variational inference for detecting topics, which adaptively balances the intrinsic complementarity between content and structure, and fully uses both local and global social contexts in topic inference. Extensive experiments on three real-world weibo datasets demonstrate the effectiveness of our proposed model.

Knowledge is essential for intelligent conversation systems to generate informative responses. This knowledge comprises a wide range of diverse modalities such as knowledge graphs (KGs), grounding documents and conversation topics. However, limited abilities in understanding language and utilizing different types of knowledge still challenge existing approaches. Some researchers try to enhance models’ language comprehension ability by employing the pre-trained language models, but they neglect the importance of external knowledge in specific tasks. In this paper, we propose a novel universal transformer-based architecture for dialogue system, the Multiple Knowledge Syncretic Transformer (MKST), which fuses multi-knowledge in open-domain conversation. Firstly, the model is pre-trained on a large-scale corpus to learn commonsense knowledge. Then during fine-tuning, we divide the type of knowledge into two specific categories that are handled in different ways by our model. While the encoder is responsible for encoding dialogue contexts with multifarious knowledge together, the decoder with a knowledge-aware mechanism attentively reads the fusion of multi-knowledge to promote better generation. This is the first attempt that fuses multi-knowledge in one conversation model. The experimental results have been demonstrated that our model achieves significant improvement on knowledge-driven dialogue generation tasks than state-of-the-art baselines. Meanwhile, our new benchmark could facilitate the further study in this research area.

Open-domain multi-turn dialogue systems are booming in human-machine interactions, which encourage to chat actively and freely in an intelligent natural way. Previous generative conversational models usually employ a single and deterministic encoder-decoder framework to model the semantic consistency between the context and corresponding response. However, they neglect the various dialog patterns (we denote the regularity of topic shifting as dialog pattern) in the conversations, leading to uninformative, non-initiative yet plausible responses. Although the existing variational methods have improved the response diversity to some extent by introducing a global variability into the generative process, they fail to simulate the transfer between topics with directional information due to the weak interpretability of the Gaussian-distributed latent variables. In this paper, we propose a novel Neural Variational Scaling Reasoning Network (NVSRN) for initiative response generation. To this end, our approach has two core ingredients: neural dialog pattern reasoner (reasoner) and topic scaling mechanism. Specifically, inspired by the advantage of von Mises-Fisher (vMF) distribution modeling the directional data (e.g., the topic transfer state), we employ it as the latent space of the reasoner to explore the regularity of topic shifting, which is then used to reason the topic of response. Based on this, a topic scaling mechanism is designed to control the transfer degree of topic in the response generator. The experimental results on two large dialog datasets demonstrate that the proposed model outperforms state-of-the-art baselines. The human evaluation shows the proposed model can produce more informative and initiative responses actively.