Link Prediction in Large Networks by Comparing the Global View of Nodes in the Network

Link prediction is an important and well-studiedproblem in network analysis, with a broad range of applicationsincluding recommender systems, anomaly detection, and denoising. The general principle in link prediction is to use thetopological characteristics of the nodes in the network to predictedges that might be added to or removed from the network. While early research utilized local network neighborhood tocharacterize the topological relationship between pairs of nodes, recent studies increasingly show that use of global networkinformation improves prediction performance. Meanwhile, in thecontext of disease gene prioritization and functional annotationin computational biology, "global topological similarity" basedmethods are shown to be effective and robust to noise andascertainment bias. These methods compute topological profilesthat represent the global view of the network from the perspectiveof each node and compare these topological profiles to assess thetopological similarity between nodes. Here, we show that, in thecontext of link prediction in large networks, the performance ofthese global-view based methods can be adversely affected byhigh dimensionality. Motivated by this observation, we proposetwo dimensionality reduction techniques that exploit the sparsityand modularity of networks that are encountered in practicalapplications. Our experimental results on predicting futurecollaborations based on a comprehensive co-authorship networkshows that dimensionality reduction renders global-view basedlink prediction highly effective, and the resulting algorithmssignificantly outperform state-of-the-art link prediction methods.