Collaborative Filtering Algorithm Based on Similarity Propagation

Collaborative filtering is one of the most widely used algorithms in the personalized recommendation system.With the increase in the number of users and items,the data sparsity becomes the important factor which affects the quality of the personalized recommendation.To address this issue,a new collaborative filtering algorithm based on the similarity propagation is introduced.The similarity between users can propagate in a limited path length as long as the similarity greater than the threshold.So the number of the nearest neighbors which is used to prediction increases and the quality of the recommendation improved because of the relief of the data sparsity.