Traditional recommender systems aim to estimate a user's rating to an item based on observed ratings from the population. As with all observational studies, hidden confounders, which are factors that affect both item exposures and user ratings, lead to a systematic bias in the estimation. Consequently, a new trend in recommender system research is to negate the influence of confounders from a causal perspective. Observing that confounders in recommendations are usually shared among items and are therefore multi-cause confounders, we model the recommendation as a multi-cause multi-outcome (MCMO) inference problem. Specifically, to remedy confounding bias, we estimate user-specific latent variables that render the item exposures independent Bernoulli trials. The generative distribution is parameterized by a DNN with factorized logistic likelihood and the intractable posteriors are estimated by variational inference. Controlling these factors as substitute confounders, under mild assumptions, can eliminate the bias incurred by multi-cause confounders. Furthermore, we show that MCMO modeling may lead to high variance due to scarce observations associated with the high-dimensional causal space. Fortunately, we theoretically demonstrate that introducing user features as pre-treatment variables can substantially improve sample efficiency and alleviate overfitting. Empirical studies on simulated and real-world datasets show that the proposed deep causal recommender shows more robustness to unobserved confounders than state-of-the-art causal recommenders. Codes and datasets are released at https://github.com/yaochenzhu/deep-deconf.
Department of Computer Science and Engineering, Hanyang University（韩阳大学计算机科学与工程系）；Department of Applied Artificial Intelligence, Hanyang University（韩阳大学应用人工智能系）
The Deconfounded Recommender: A Causal Inference Approach to Recommendation
Columbia University（哥伦比亚大学）；Netflix Inc.（奈飞公司）；Mila；HEC Montréal（蒙特利尔高等商学院）
推荐的目标是向用户展示他们喜欢的项目。虽然通常被框定为预测，但推荐的精神是回答一个介入性的问题-对于每个用户和电影，如果我们“强迫”用户观看电影，评分会是多少？为此，我们开发了一种因果推荐方法，其中观看电影是一种“治疗”，用户的评级是一种“结果”。“问题是可能存在未观察到的混杂因素，这些变量影响用户观看的电影以及他们如何评价它们;未观察到的混杂因素阻碍了观察数据的因果预测。为了解决这个问题，我们开发了去基推荐器，一种使用经典推荐模型进行因果推荐的方法。在Wang & Blei [23]之后，去基推荐器涉及两个概率模型。第一个模型是用户观看的电影;它为未观察到的混杂因素提供了替代品。第二个模型模拟每个用户如何评价每部电影;它使用替代品来帮助解释混淆因素。这种两阶段方法消除了由于混淆而导致的偏倚。它改善了推荐，并在测试集上具有稳定的性能。
Causal Structure Representation Learning of Confounders in Latent Space for Recommendation
MIC Lab, College of Computer Science and Technology, Jilin University（吉林大学计算机科学与技术学院MIC实验室）；Key Laboratory of Trustworthy Distributed Computing and Service (MoE), Beijing University of Posts and Telecommunications（北京邮电大学可信分布式计算与服务重点实验室）；Institute of Artificial Intelligence, Beihang University and Zhongguancun Laboratory（北航人工智能研究院和中关村实验室）
A General Neural Causal Model for Interactive Recommendation
Computer Network Information Center, Chinese Academy of Sciences（中国科学院计算机网络信息中心）；University of Chinese Academy of Sciences（中国科学院大学）；Chinese University of Hong Kong（香港中文大学）；City University of Hong Kong（香港城市大学）
Towards Generalizable Reasoning: Group Causal Counterfactual Policy Optimization for LLM Reasoning
Institute of Software, Chinese Academy of Sciences（中国科学院软件研究所）；University of Chinese Academy of Sciences（中国科学院大学）；Wangxuan Institute of Computer Technology, Peking University（北京大学王宣计算机技术研究所）；The Hong Kong University of Science and Technology (Guangzhou)（香港科技大学（广州））
From Observational Data to Clinical Recommendations: A Causal Framework for Estimating Patient-level Treatment Effects and Learning Policies
Faculty of Data and Decision Sciences, Technion（数据与决策科学学院，技术ion）；Blavatnik School of Computer Science, Tel-Aviv University（Blavatnik计算机科学学院，特拉维夫大学）；Department of Cardiology, Rambam Health Care Campus（心内科部，拉马姆医疗中心）；The Bruce Rappaport Faculty of Medicine, Technion（布鲁斯·拉帕波特医学院，技术ion）；Department of Statistics and Operations Research, School of Mathematical Sciences, Tel Aviv University（统计与运筹学部，数学科学学院，特拉维夫大学）
Unveiling Causal Reasoning in Large Language Models: Reality or Mirage?
Intelligent Game and Decision Lab（智能游戏与决策实验室）；National University of Defense Technology（国防科技大学）；University of Melbourne（墨尔本大学）；University of Sydney（悉尼大学）；Hong Kong Baptist University（香港 Baptist 大学）
ChainReaction: Causal Chain-Guided Reasoning for Modular and Explainable Causal-Why Video Question Answering
Institute of High Performance Computing, Agency for Science, Technology and Research, Singapore（新加坡高性能计算研究所，科技研究局）；Centre for Frontier AI Research, Agency for Science, Technology and Research, Singapore（科技研究局前沿人工智能研究中心，新加坡）；College of Computing and Data Science, Nanyang Technological University, Singapore（新加坡南洋理工大学计算与数据科学学院）
