Link Recommendations for PageRank Fairness

Abstract

Network algorithms play a critical role in various applications, such as recommendations, diffusion maximization, and web search. In this paper, we focus on the fairness of such algorithms and in particular of PageRank. PageRank fairness refers to a fair allocation of the PageRank weights among the nodes. We consider the effect of the network structure on PageRank fairness. Concretely, we provide analytical formulas for computing the effect of edge additions on fairness and for the conditions that an edge must satisfy so that its addition improves fairness. We also provide analytical formulas for evaluating the role of existing edges in fairness. We use our findings to propose efficient linear time link recommendation algorithms for maximizing fairness, and we evaluate them on real datasets. Our approach can be seen as an effort towards making the network itself fairer as opposed to making fairer the network algorithms, or their outputs.