arXiv AI

Neither Black nor White: Balancing Semantic and Collaborative Signals with Graph-Informed Semantic IDs (GrIS)

The paper introduces Graph-Informed Semantic IDs (GrIS), a framework that reframes Semantic ID construction as a recursive clustering problem on a graph combining semantic content and collaborative signals. GrIS generalises previous methods like RQ-VAE and RQ-KMeans by allowing explicit graph construction and hierarchical partitioning, and presents two implementations: RecDMoN and RQ-GAE. Experiments on real-world datasets show that GrIS outperforms collaborative-filtering aware state‑of‑the‑art models, achieving up to a 52% increase in Hit@10.

arXiv AI
Sep 10

Exploring Bottom-Up Clustering for Creating Semantic IDs

The paper proposes a new algorithm for generating Semantic IDs that are both unique and preserve the structure of the original embedding space. By employing bottom‑up clustering, the method maintains local structure, leading to higher clustering quality. This improved structure enhances the utility of the Semantic IDs for downstream generative retrieval tasks.

By Leah Woldemariam, Sudhanshu Garg, Taha Belkhouja, Charles Kim-Yip, Ali Sahami
arXiv AI
4d ago

FineSID: Scalable and Efficient Semantic Identifier Learning for Generative Recommendation

FineSID introduces a new quantization framework for semantic identifier learning in generative recommendation systems. By replacing the traditional Top‑1 hard assignment with a soft, differentiable approach, it distributes gradient updates across all codewords, leading to balanced codebook optimization and reduced identifier collisions. Experiments on public benchmarks show that FineSID improves codebook utilization and recommendation accuracy without relying on complex initialization strategies.

By Song-Li Wu, Weinan Gan, Zhaocheng Du, Xianquan Wang, Jingyi Wang
arXiv AI
Jun 8

Understanding Generative Recommendation with Semantic IDs from a Model-scaling View

arXiv:2509. 25522v3 Announce Type: replace Abstract: Recent advancements in generative models have allowed the emergence of a promising paradigm for recommender systems (RS), known as Generative Recommendation (GR), which tries to unify rich item semantics and collaborative filtering signals.

By Jingzhe Liu, Liam Collins, Jiliang Tang, Tong Zhao, Neil Shah, Clark Mingxuan Ju
arXiv AI
Aug 28

Refine-POI: Reinforcement Fine-Tuned Large Language Models for Next Point-of-Interest Recommendation

Refine-POI introduces a reinforcement fine-tuned framework for next point-of-interest recommendation that tackles two key issues: topology-blind indexing of semantic IDs and the limitation of supervised fine-tuning to top‑1 predictions. It uses a hierarchical self‑organizing map to generate topology‑aware semantic IDs and a policy‑gradient approach to produce top‑k recommendation lists. Experiments on three real‑world datasets show that Refine‑POI outperforms state‑of‑the‑art baselines, combining LLM reasoning with accurate, explainable recommendations.

By Peibo Li, Shuang Ao, Hao Xue, Yang Song, Maarten de Rijke, Johan Barth\'elemy, Tomasz Bednarz, Flora D. Salim
arXiv Machine Learning
Aug 11

Preserving Item Semantics for Free: Rethinking Token Initialization in LLM-Based Generative Recommendation

arXiv:2608. 07816v1 Announce Type: cross Abstract: Recent advances in generative recommendation (GR) leverage large language models (LLMs) as recommender backbones, enabling LLMs to directly generate recommendations conditioned on item-interaction histories.

By Donald Loveland, Liam Collins, Bhuvesh Kumar, Danai Koutra, Neil Shah
arXiv AI
Jun 26

The Best of the Two Worlds: Harmonizing Semantic and Hash IDs for Sequential Recommendation

arXiv:2512. 10388v3 Announce Type: replace-cross Abstract: Conventional Sequential Recommender Systems (SRS) typically assign unique hash IDs (HID) to construct item embeddings, which mainly capture collaborative signals from historical user-item interactions.

By Ziwei Liu, Yejing Wang, Wanyu Wang, Wang Zejian, Qidong Liu, Zijian Zhang, Chong Chen, Wei Huang, Xiangyu Zhao
arXiv AI
Jun 10

Reasoning over Semantic IDs Enhances Generative Recommendation

arXiv:2603. 23183v2 Announce Type: replace-cross Abstract: Recent advances in generative recommendation have leveraged pretrained LLMs by formulating sequential recommendation as autoregressive generation over a unified token space comprising language tokens and itemic identifiers, where each item is represented by a compact sequence of discrete tokens, namely Semantic IDs (SIDs).

By Yingzhi He, Yan Sun, Junfei Tan, Yuxin Chen, Xiaoyu Kong, Chunxu Shen, Xiang Wang, An Zhang, Tat-Seng Chua