Expanded graph embedding for joint network alignment and link prediction

Link prediction in social networks has been an active field of study in recent years fueled by the rapid growth of many social networks. Many link prediction methods are harmed by users' intention of avoiding being traced across networks. They may provide inaccurate information or overlook a great deal of information in multiple networks. This problem was overcome by developing methods for predicting links in a network based on known links in another network. Node alignment between the two networks significantly improves the efficiency of those methods. This research proposes a new embedding method to improve link prediction and node alignment results. The proposed embedding method is based on the Expanded Graph, which is our new novel network that has edges from both networks in addition to edges across the networks. Matrix factorization on the Finite Step Transition and Laplacian similarity matrices of the Expanded Graph has been used to obtain the embeddings for the nodes. Using the proposed embedding techniques, we jointly run network alignment and link prediction tasks iteratively to let them optimize each other's results. We performed extensive experiments on many datasets to examine the proposed method. We achieved significant improvements in link prediction precision, which was 50% better than the peer's method, and in recall, which was 500% better in some datasets. We also scale down the processing time of the solution to be more applicable to big social networks. We conclude that computed embedding in this type of problem is more suitable than learning the embedding since it shortens the processing time and gives better results.