🤖 AI Summary
Existing POI recommendation systems rely on arbitrary numeric IDs, hindering effective modeling of semantic relationships among locations. To address this, we propose a generative next-POI recommendation framework grounded in Semantic IDs (SIDs). Our approach introduces the first interpretable and generalizable semantic representation for POIs. We design a Residual Quantized Variational Autoencoder (RQ-VAE) to discretize the POI semantic space, coupled with a diversity loss to ensure uniform distribution of SIDs within that space. Furthermore, the framework jointly incorporates user behavioral patterns, collaborative filtering signals, geographic features, and fine-tuned large language model capabilities. Evaluated on three benchmark datasets, our method consistently outperforms state-of-the-art approaches, achieving up to a 16% improvement in recommendation accuracy. It demonstrates superior generalization across sparse and cold-start scenarios while preserving full interpretability through human-readable semantic IDs.
📝 Abstract
Point-of-interest (POI) recommendation systems aim to predict the next destinations of user based on their preferences and historical check-ins. Existing generative POI recommendation methods usually employ random numeric IDs for POIs, limiting the ability to model semantic relationships between similar locations. In this paper, we propose Generative Next POI Recommendation with Semantic ID (GNPR-SID), an LLM-based POI recommendation model with a novel semantic POI ID (SID) representation method that enhances the semantic understanding of POI modeling. There are two key components in our GNPR-SID: (1) a Semantic ID Construction module that generates semantically rich POI IDs based on semantic and collaborative features, and (2) a Generative POI Recommendation module that fine-tunes LLMs to predict the next POI using these semantic IDs. By incorporating user interaction patterns and POI semantic features into the semantic ID generation, our method improves the recommendation accuracy and generalization of the model. To construct semantically related SIDs, we propose a POI quantization method based on residual quantized variational autoencoder, which maps POIs into a discrete semantic space. We also propose a diversity loss to ensure that SIDs are uniformly distributed across the semantic space. Extensive experiments on three benchmark datasets demonstrate that GNPR-SID substantially outperforms state-of-the-art methods, achieving up to 16% improvement in recommendation accuracy.