Mu Xu
2026
Reasoning Over Space: Enabling Geographic Reasoning for LLM-Based Generative Next POI Recommendation
Dongyi Lv | Qiuyu Ding | Heng-Da Xu | Zhaoxu Sun | Zhi Wang | Feng Xiong | Mu Xu
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Dongyi Lv | Qiuyu Ding | Heng-Da Xu | Zhaoxu Sun | Zhi Wang | Feng Xiong | Mu Xu
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Generative recommendation with large language models (LLMs) reframes prediction as sequence generation, yet existing LLM-based recommenders remain limited in leveraging geographic signals that are crucial in mobility and local-services scenarios. Here, we present Reasoning Over Space (ROS), a framework that utilizes geography as a vital decision variable within the reasoning process. ROS introduces a Hierarchical Spatial Semantic ID (SID) that discretizes coarse-to-fine locality and POI semantics into compositional tokens, and endows LLM with a three-stage Mobility Chain-of-Thought (CoT) paradigm that models user personality, constructs an intent-aligned candidate space, and performs locality informed pruning. We further align the model with real world geography via spatial-guided Reinforcement Learning (RL). Experiments on three widely used location-based social network (LBSN) datasets show that ROS achieves over 10% relative gains in hit rate over strongest LLM-based baselines and improves cross-city transfer, despite using a smaller backbone model.
2019
Generating Responses with a Specific Emotion in Dialog
Zhenqiao Song | Xiaoqing Zheng | Lu Liu | Mu Xu | Xuanjing Huang
Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics
Zhenqiao Song | Xiaoqing Zheng | Lu Liu | Mu Xu | Xuanjing Huang
Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics
It is desirable for dialog systems to have capability to express specific emotions during a conversation, which has a direct, quantifiable impact on improvement of their usability and user satisfaction. After a careful investigation of real-life conversation data, we found that there are at least two ways to express emotions with language. One is to describe emotional states by explicitly using strong emotional words; another is to increase the intensity of the emotional experiences by implicitly combining neutral words in distinct ways. We propose an emotional dialogue system (EmoDS) that can generate the meaningful responses with a coherent structure for a post, and meanwhile express the desired emotion explicitly or implicitly within a unified framework. Experimental results showed EmoDS performed better than the baselines in BLEU, diversity and the quality of emotional expression.