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贝叶斯矩阵有限分解:变分算法和补习é罗界

Bayesian Matrix Co-Factorization: Variational Algorithm and Cramér-Rao Bound
课程网址: http://videolectures.net/ecmlpkdd2011_choi_matrix/  
主讲教师: Seungjin Choi
开课单位: 浦项科技大学
开课时间: 2011-11-30
课程语种: 英语
中文简介:
矩阵分解法是一种常用的协同预测方法,其中用户和项目因子矩阵预测未知的评分,确定近似用户项目矩阵作为其产品。在协同过滤中,贝叶斯矩阵因式分解比其他方法更受欢迎,因为贝叶斯方法减少了过度拟合,使用变分推理或抽样方法整合了所有模型参数。然而,贝叶斯矩阵因式分解仍然存在冷启动问题,需要预测新项目的评级或新用户的偏好。本文将贝叶斯矩阵共因式分解作为一种利用诸如内容信息和人口统计用户数据等边信息的方法,其中多个数据矩阵被联合分解,即每个贝叶斯分解通过共享一些因子矩阵来耦合。推导了贝叶斯矩阵共因式分解的变分推理算法。此外,我们计算了高斯似然情况下的贝叶斯CRAMé;r-rao界,表明贝叶斯矩阵共因子分解确实改善了单数据矩阵的贝叶斯因子分解重构。数值实验证明了贝叶斯矩阵共因式分解在冷启动问题中的有效性。
课程简介: Matrix factorization is a popular method for collaborative prediction, where unknown ratings are predicted by user and item factor matrices which are determined to approximate a user-item matrix as their product. Bayesian matrix factorization is preferred over other methods for collaborative filtering, since Bayesian approach alleviates overfitting, integrating out all model parameters using variational inference or sampling methods. However, Bayesian matrix factorization still suffers from the cold-start problem where predictions of ratings for new items or of new users' preferences are required. In this paper we present Bayesian matrix co-factorization as an approach to exploiting side information such as content information and demographic user data, where multiple data matrices are jointly decomposed, i.e., each Bayesian decomposition is coupled by sharing some factor matrices. We derive variational inference algorithm for Bayesian matrix co-factorization. In addition, we compute Bayesian Cramér-Rao bound in the case of Gaussian likelihood, showing that Bayesian matrix co-factorization indeed improves the reconstruction over Bayesian factorization of single data matrix. Numerical experiments demonstrate the useful behavior of Bayesian matrix co-factorization in the case of cold-start problems.
关 键 词: 矩阵分解; 收视率预测; 协分解
课程来源: 视频讲座网
最后编审: 2019-11-28:lxf
阅读次数: 73