Overview
Personalization is key in understanding user behavior and has been a main focus in the fields of knowledge discovery and information retrieval. Building personalized recommender systems is especially important now due to the vast amount of user-generated textual content, which offers deep insights into user preferences. The recent advancements in Large Language Models (LLMs) have significantly impacted research areas, mainly in Natural Language Processing and Knowledge Discovery, giving these models the ability to handle complex tasks and learn context.
However, the use of generative models and user-generated text for personalized systems and recommendation is relatively new and has shown some promising results. This workshop is designed to bridge the research gap in these fields and explore personalized applications and recommender systems. We aim to fully leverage generative models to develop AI systems that are not only accurate but also focused on meeting individual user needs. Building upon the momentum of previous successful forums, this workshop seeks to engage a diverse audience from academia and industry, fostering a dialogue that incorporates fresh insights from key stakeholders in the field.
Call for papers
Deadline extended to 10 June 2024. We will welcome papers that leverage generative models with a goal of recommendation and personalization on several topics including but not limited to those mentioned in CFP. Papers can be submitted at OpenReview.
Information for the day of the workshop
Workshop at KDD2024
- Submission deadline:
28 May 202410 June 2024 - Author notifications: 28 June 2024
- Meeting: 25/26 August 2024
Schedule
Time (PDT) | Agenda |
---|---|
2:00-2:10pm | Opening remarks |
2:10-2:50pm | Keynote by Dietmar Jannach (40 min) |
2:50-3:30pm | Coffee Break/Poster Session |
3:30-4:10pm | Keynote by Xiao-Ming (40 min) |
4:15-4:55pm | Keynote by Ed Chi (40 min) |
5:00-6:00pm | Panel Discussion (60 min) Panelists: Ed Chi, James Caverlee, Huzefa Rangwala, Xiao-Ming Wu |
Keynote Speakers
Ed Chi
Google DeepMind
The Future of Discovery Assistance
Dietmar Jannach
University of Klagenfurt, University of Bergen
Title of the talk: Leveraging Large Language Models for Recommender Systems
Xiao-Ming Wu
The Hong Kong Polytechnic University
Title of the talk: Advancing Next-Generation Recommendation Models with Large Language Models
Panelists
Ed Chi
Google DeepMind
Xiao-Ming Wu
The Hong Kong Polytechnic University
James Caverlee
Texas A&M University
Yashar Deldjoo
Polytechnic University of Bari, Italy
Huzefa Rangwala
AWS AI Labs
Accepted Papers
- SUBER An RL Environment with Simulated Human Behavior for Recommender Systems
Nathan Corecco, Giorgio Piatti, Luca A Lanzendörfer, Flint Xiaofeng Fan, Roger WattenhoferAbstractAbstract: Reinforcement learning (RL) has gained popularity in the realm of recommender systems due to its ability to optimize long-term rewards and guide users in discovering relevant content. However, the successful implementation of RL in recommender systems is challenging because of several factors, including the limited availability of online data for training on-policy methods. This scarcity requires expensive human interaction for online model training. Furthermore, the development of effective evaluation frameworks that accurately reflect the quality of models remains a fundamental challenge in recommender systems. To address these challenges, we propose a comprehensive framework for synthetic environments that simulate human behavior by harnessing the capabilities of large language models (LLMs). We complement our framework with in-depth ablation studies and demonstrate its effectiveness with experiments on movie and book recommendations. By utilizing LLMs as synthetic users, this work introduces a modular and novel framework for training RL-based recommender systems. The software, including the RL environment, is publicly available.PDF Code - ECCR Explainable and Coherent Complement Recommendation based on Large Language Models
Zelong Li, Yan Liang, Ming Wang, Sungro Yoon, Jiaying Shi, Xin Shen, Xiang He, Chenwei Zhang, Wenyi Wu, Hanbo Wang, Jin Li, Jim Chan, Yongfeng ZhangAbstractAbstract: A complementary item is an item that pairs well with another item when consumed together. In the context of e-commerce, providing recommendations for complementary items is essential for both customers and stores. Current models for suggesting complementary items often rely heavily on user behavior data, such as co-purchase relationships. However, just because two items are frequently bought together does not necessarily mean they are truly complementary. Relying solely on co-purchase data may not align perfectly with the goal of making meaningful complementary recommendations. In this paper, we introduce the concept of "coherent complement recommendation", where "coherent" implies that recommended item pairs are compatible and relevant. Our approach builds upon complementary item pairs, with a focus on ensuring that recommended items are well used together and contextually relevant. To enhance the explainability and coherence of our complement recommendations, we fine-tune the Large Language Model (LLM) with coherent complement recommendation and explanation generation tasks since LLM has strong natural language explanation generation ability and multi-task fine-tuning enhances task understanding. We have also devised an LLM-compatible method for compressing and quantizing user behavior information into language model tokens. Experimental results indicate that our model can provide more coherent complementary recommendations than existing state-of-the-art methods, and human evaluation validates that our approach achieves up to a 48% increase in the coherent rate of complement recommendations.PDF Code - HindRec Aligning User Preferences for Recommendation via Hindsight Fine-tuning
Yawen Zeng, huanwen wang, Lingyu Chen, Wenshu Chen, chenran, Hao ChenAbstractAbstract: Given a user's historical interaction sequence, the recommendation model strives to understand the user's preferences and predict potential candidate items. Presently, the surging popularity of large language models (LLMs) has birthed an array of generative recommendation systems. However, the unfortunate drawback of merging LLMs into recommendation systems is that it cannot capture the true preferences of users (i.e., likes and dislikes). In this paper, we venture to combine alignment techniques in LLMs to align interest preferences. Specifically, this paper first proposes the application of hindsight fine-tuning in generative recommendation model—referred to as HindRec—which includes three components: prompt construction, recommendation via LLM and hindsight fine-tuning. By constructing training data in the form of hindsight feedback, we fine-tune a LLM via a three-stage strategy to fully utilize positive and negative instances to align user preferences. Wide-ranging experimental corroboration of our HindRec has yielded truly significant outcomes.PDF Code - EDGE-Rec Efficient and Data-Guided Edge Diffusion For Recommender Systems Graphs
Utkarsh Priyam, Hemit Shah, Edoardo BottaAbstractAbstract: Most recommender systems research focuses on binary historical user-item interaction encodings to predict future interactions. User features, item features, and interaction strengths remain largely under-utilized in this space or only indirectly utilized, despite proving largely effective in large-scale production recommendation systems. We propose a new attention mechanism, loosely based on the principles of collaborative filtering, called Row-Column Separable Attention $(\textbf{RCSA})$ to take advantage of real-valued interaction weights as well as user and item features directly. Building on this mechanism, we additionally propose a novel Graph Diffusion Transformer $(\textbf{GDiT})$ architecture which is trained to iteratively denoise the weighted interaction matrix of the user-item interaction graph directly. The weighted interaction matrix is built from the bipartite structure of the user-item interaction graph and corresponding edge weights derived from user-item rating interactions. Inspired by the recent progress in text-conditioned image generation, our method directly produces user-item rating predictions on the same scale as the original ratings by conditioning the denoising process on user and item features with a principled approach.PDF Code - Optimizing Novelty of Top-k Recommendations using Large Language Models and Reinforcement Learning
Amit Sharma, Hua Li, Xue Li, Jian JiaoAbstractAbstract: Given an input query, a recommendation model is trained using user feedback data (e.g., click data) to output a ranked list of items. In real-world systems, besides accuracy, an important consideration for a new model is novelty of its top-k recommendations w.r.t. an existing deployed model. However, novelty of top-k items is a difficult goal to optimize a model for, since it involves a non-differentiable sorting operation on the model's predictions. Moreover, novel items, by definition, do not have any user feedback data. Given the semantic capabilities of large language models, we address these problems using a reinforcement learning (RL) formulation where large language models provide feedback for the novel items. However, given millions of candidate items, the sample complexity of a standard RL algorithm can be prohibitively high. To reduce sample complexity, we reduce the top-k list reward to a set of item-wise rewards and reformulate the state space to consist of tuples such that the action space is reduced to a binary decision; and show that this reformulation results in a significantly lower complexity when the number of items is large. We evaluate the proposed algorithm on improving novelty for a query-ad recommendation task on a large-scale search engine. Compared to supervised finetuning on recent pairs, the proposed RL-based algorithm leads to significant novelty gains with minimal loss in recall. We get similar results on the ORCAS dataset for matching queries to web pages.PDF Code - Active Users are Good Teachers, Behavior Sequence Infilling for Generative Recommendation
Qijiong Liu, Xiaoyu DONG, Quanyu Dai, Jieming Zhu, Zhenhua Dong, Xiao-Ming WuAbstractAbstract: The training of recommender systems relies on user behavior data, which are typically heavily unbalanced: active users, who generate more interactions, are likely to be favored in the recommendation process, while inactive users may receive unsatisfactory recommendations, resulting in low customer retention. To mitigate this problem, we propose beahvior sequence infilling (**BeSI**), a novel generative approach for sequential recommendation. BeSI seeks to fill the *trend gaps* in inactive user behavior sequences through the design of a trend gap meter to measure behavior coherence and a beahvior sequence infiller to generate smoother and richer behavior sequences. BeSI is model-agnostic and can be easily integrated with any existing sequential recommendation model. We will release data and code for other researchers to reproduce our results.PDF Code - Policy optimization of language models to align fidelity and efficiency of generative retrieval in multi-turn dialogues
Jeremy CuruksuAbstractAbstract: Reinforcement learning from human preferences can fine tune language models for helpfulness and safety, but does not directly address the fidelity and efficiency of reasoning agents in multi-turn dialogues. We propose a method to improve the validity, coherence and efficiency of reasoning agents by defining a reward model as a mapping between predefined queries and tools which can be applied to any custom orchestration environment. The reward model is used for policy optimization to fine tune the clarification fallback behavior and help the agent learn when best to ask for clarifications in multi-turn dialogues. This is demonstrated in several orchestration environments where after fine tuning with either proximal policy optimization or verbal reinforcement, the new policy systematically identifies the correct intents and tools in < 2 steps in over 99% of all sampled dialogues.PDF Code - PERSOMA PERsonalized SOft ProMpt Adapter Architecture for Personalized Language Prompting
Liam Hebert, Krishna Sayana, Ambarish Jash, Alexandros Karatzoglou, Sukhdeep Sodhi, Sumanth Doddapaneni, Yanli Cai, Dima KuzminAbstractAbstract: Understanding the nuances of a user's extensive interaction history is key to building accurate and personalized natural language systems that can adapt to evolving user preferences. To address this, we introduce PERSOMA, Personalized Soft Prompt Adapter architecture. Unlike previous personalized prompting methods for large language models, PERSOMA offers a novel approach to efficiently capture user history. It achieves this by resampling and compressing interactions as free form text into expressive soft prompt embeddings, building upon recent research utilizing embedding representations as input for LLMs. We rigorously validate our approach by evaluating various adapter architectures, first-stage sampling strategies, parameter-efficient tuning techniques like LoRA, and other personalization methods. Our results demonstrate PERSOMA's superior ability to handle large and complex user histories compared to existing embedding-based and text-prompt-based techniques.PDF Code - LLMs for User Interest Exploration in Large-scale Recommendation Systems
Jianling Wang, Haokai Lu, Yifan Liu, He Ma, Yueqi Wang, Yang Gu, Shuzhou Zhang, Ningren Han, Shuchao Bi, Lexi Baugher, Ed H. Chi, Minmin ChenAbstractAbstract: Traditional recommendation systems are subject to a strong feedback loop by learning from and reinforcing past user-item interactions, which in turn limits the discovery of novel user interests. To address this, we introduce a hybrid hierarchical framework combining Large Language Models (LLMs) and classic recommendation models for user interest exploration. The framework controls the interfacing between the LLMs and the classic recommendation models through "interest clusters", the granularity of which can be explicitly determined by algorithm designers. It recommends the next novel interests by first representing "interest clusters" using language, and employs a fine-tuned LLM to generate novel interest descriptions that are strictly within these predefined clusters. At the low level, it grounds these generated interests to an item-level policy by restricting classic recommendation models, in this case a transformer-based sequence recommender to return items that fall within the novel clusters generated at the high level. We showcase the efficacy of this approach on an industrial-scale commercial platform serving billions of users. Live experiments show a significant increase in both exploration of novel interests and overall user enjoyment of the platform."PDF Code - Meta Knowledge for Retrieval Augmented Large Language Models
Laurent Mombaerts, Tianyu Ding, Florian Felice, Adi Banerjee, Jonathan Taws, Tarik BorogovacAbstractAbstract: Retrieval Augmented Generation (RAG) is a technique used to augment Large Language Models (LLMs) with contextually relevant, time-critical, or domain-specific information without altering the underlying model parameters. However, constructing RAG systems that can effectively synthesize information from large and diverse set of documents remains a significant challenge. We introduce a novel data-centric RAG workflow for LLMs, transforming the traditional retrieve-then-read system into a more advanced prepare- then-rewrite-then-retrieve-then-read framework, to achieve higher domain expert-level understanding of the knowledge base. Our methodology relies on generating metadata and synthetic Questions and Answers (QA) for each document, as well as introducing the new concept of Meta Knowledge Summary (MK Summary) for metadata-based clusters of documents. The proposed innovations enable personalized user-query augmentation and in-depth information retrieval across the knowledge base. Our research makes two significant contributions: using LLMs as evaluators and em- ploying new comparative performance metrics, we demonstrate that (1) using augmented queries with synthetic question matching significantly outperforms traditional RAG pipelines that rely on document chunking (𝑝 < 0.01), and (2) meta knowledge-augmented queries additionally significantly improve retrieval precision and recall, as well as the final answer’s breadth, depth, relevancy, and specificity. Our methodology is cost-effective, costing less than $20 per 2000 research papers using Claude 3 Haiku, and can be adapted with any fine-tuning of either the language or embedding models to further enhance the performance of end-to-end RAG pipelines.PDF Code - Survey for Landing Generative AI in Social and E-commerce Recsys – the Industry Perspectives
Da Xu, Danqing Zhang, Guangyu Yang, bo yang, Shuyuan Xu, lingling zheng, Cindy LiangAbstractAbstract: Recently, generative AI (GAI), with their emerging capabilities, have presented unique opportunities for augmenting and revolutionizing industrial recommender systems (Recsys). Despite growing research efforts at the intersection of these fields, the integration of GAI into industrial Recsys remains in its infancy, largely due to the intricate nature of modern industrial Recsys infrastructure, operations, and product sophistication. Drawing upon our experiences in successfully integrating GAI into several major social and e-commerce platforms, this survey aims to comprehensively examine the underlying system and AI foundations, solution frameworks, connections to key research advancements, as well as summarize the practical insights and challenges encountered in the endeavor to integrate GAI into industrial Recsys. As pioneering work in this domain, we hope outline the representative developments of relevant fields, shed lights on practical GAI adoptions in the industry, and motivate future research.PDF Code - Evaluation of Refined Conversational Recommendation Based on Reprompting ChatGPT with Feedback
Kyle Dylan Spurlock, Cagla Acun, Esin Saka, Olfa NasraouiAbstractAbstract: Recommendation algorithms seldom consider direct user input, resulting in superficial interaction between them despite efforts to include the user through conversation. Recently, Large Language Models (LLMs) have gained popularity across a number of domains for their extensive knowledge and transfer learning capabilities. For instance, ChatGPT boast impressive interactivity and an easy-to-use interface. In this paper, we investigate the effectiveness of ChatGPT as a top-n conversational recommendation system. We build a rigorous evaluation pipeline to simulate how a user might realistically probe the model for recommendations: by first instructing and then reprompting with feedback to refine the recommendations. We further explore the effect of popularity bias in ChatGPT's recommendations, and compare its performance to baseline recommendation models. We find that reprompting with feedback is an effective strategy to improve recommendation relevancy, and that popularity bias can be mitigated through prompt engineering.PDF Code
Organizers
Narges Tabari:
AWS AI Labs
Aniket Deshmukh
AWS AI Labs
Wang-Cheng Kang
Google DeepMind
Rashmi Gangadharaiah
AWS AI Labs
Hamed Zamani
University of Massachusetts Amherst
Julian McAuley
University of California, San Diego
George Karypis
University of Minnesota
Program Committee
- ABC (XYZ University)