基于LU分解和交替最小二乘法的分布式奇异值分解推荐算法

针对当前分布式潜在因子推荐算法存在时间复杂度较高、运行时间较长的问题,文中提出基于LU分解和交替最小二乘法(ALS)的分布式奇异值分解推荐算法,利用ALS利于分布式求解目标函数的特点,提出网格状分布式粒度分割策略,获取相互独立不相关的特征向量.在更新特征矩阵时,使用LU分解求逆矩阵,加快算法的运行速度.在KDD CUP 2012 Track1中的腾讯微博数据集上的实验表明,文中算法在确保一定推荐精度的前提下,大幅提升推荐速度和算法效率.

Distributed Singular Value Decomposition Recommendation Algorithm Based on LU Decomposition and Alternating Least Square

Aiming at the problems of high time complexity and long running time of the current distributed potential factor recommendation algorithm,a distributed singular value decomposition recommendation algorithm based on LU decomposition and alternating least square(ALS)is proposed.Based on the characteristics of ALS for distributed solution of objective function,a grid-like distributed granularity segmentation strategy is proposed to obtain independent and unrelated feature vectors.When the characteristic matrix is updated,LU decomposition is adopted to solve the inverse matrix to speed up the operation of the algorithm.The experiment on Tencent Weibo dataset in KDD CUP 2012 Track1 indicates that the recommendation speed and efficiency of the proposed algorithm is significantly improved on the premise of ensuring a certain recommendation accuracy.