目标PageRank:通过预算受限的加边匹配指定PageRank分数
Target PageRank: Matching Prescribed PageRank Scores via Budgeted Edge Additions
Parth Gupta, Abhinav Jain, Avishek Mukhopadhyay, Amitabha Bagchi, Sayan Ranu, Abhijnan Chakraborty
AI 速读 基于摘要
研究在恰好添加B条边的预算下,如何通过加边使目标节点的PageRank逼近给定目标向量,并给出计算复杂性结果与启发式算法。
cs.SI
查看原文摘要
PageRank is widely used to quantify the importance of nodes in directed networks. In applications such as recommendation systems, it is increasingly important that the PageRank distribution provides a fair representation of node exposure. This motivates the problem of making minimal changes to a graph so that the PageRank values of a given set of target nodes $T$ match a desired vector $\boldsymbol{t}$. In this paper, we study this problem under an edge-addition budget $B$, where exactly $B$ edges may be added to the graph. We show that deciding whether a multiset of exactly $B$ added edges can make the target nodes attain their desired absolute PageRank scores is NP-complete. After this, we define the $\ell_1$ \textsc{Target PageRank} problem in which we seek to minimize the $\ell_1$ distance between the target vector and resultant vector. We show that this optimization problem admits no polynomial-time multiplicative constant-factor approximation unless $P=NP$. Motivated by these hardness results, we propose two greedy heuristics for approaching the target PageRank vector. We additionally propose a Random Walk Hungarian (RWH) heuristic that addresses the addition of edges between dissimilar nodes by incorporating a penalty for such edges. Finally, we evaluate the proposed heuristics on several real-world and synthetic datasets and compare their performance in terms of PageRank accuracy, computational efficiency, and the relevance of the added edges.