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arXiv · 1204.1949

Social Recommender Systems Based on Coupling Network Structure Analysis

Abstract

The past few years has witnessed the great success of recommender systems, which can significantly help users find relevant and interesting items for them in the information era. However, a vast class of researches in this area mainly focus on predicting missing links in bipartite user-item networks (represented as behavioral networks). Comparatively, the social impact, especially the network structure based properties, is relatively lack of study. In this paper, we firstly obtain five corresponding network-based features, including user activity, average neighbors' degree, clustering coefficient, assortative coefficient and discrimination, from social and behavioral networks, respectively. A hybrid algorithm is proposed to integrate those features from two respective networks. Subsequently, we employ a machine learning process to use those features to provide recommendation results in a binary classifier method. Experimental results on a real dataset, Flixster, suggest that the proposed method can significantly enhance the algorithmic accuracy. In addition, as network-based properties consider not only the social activities, but also take into account user preferences in the behavioral networks, therefore, it performs much better than that from either social or behavioral networks. Furthermore, since the features based on the behavioral network contain more diverse and meaningfully structural information, they play a vital role in uncovering users' potential preference, which, might show light in deeply understanding the structure and function of the social and behavioral networks.

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Xiao Hu, Chuibo Chen, Xiaolong Chen, Zi-Ke Zhang. 2012-04-09. Social Recommender Systems Based on Coupling Network Structure Analysis. https://arxiv.org/abs/1204.1949

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