Identification And Application Of A Set Of Vital Nodes On Complex Network

The vital nodes in a complex network are those nodes that play an important role in the structure and function of the network.Scholars have put forward many algorithms of vital nodes identification from different perspectives.However,in some real-world applications,a small set of nodes plays a key role,which is called a set of vital nodes.For example,how to choose a set of fewer nodes make the information spread the largest in dissemination of information? Under a certain budget,how to select a specific group of users so that advertising can be known to more users?In recent years,from influence maximization problem to finding the most influential spreaders,many scholars have conducted in-depth research on this issue.The algorithm form is changed from the early greedy algorithm and its improvement to the heuristic algorithm which is more common in recent years.Based on some recently heuristic algorithms,this paper analyzes and proposes a new algorithm of identification of a set of vital nodes based on the importance of nodes and the distance between nodes.The main research contents and innovations of this paper are as follows:(1)The paper proposes an algorithm of identification of vital nodes based on improved coreness entropy.This article believes that the importance of nodes is not only related to the number of nodes' coreness,but also related to the diversity of the coreness of directly connected neighbors.Moreover,in order to eliminate the influence of degree on the coreness entropy,the paper improves and proposes the coreness entropy and proposes the MKE algorithm.(2)By analyzing the similarity of nodes and based on the algorithm of finding communities by their centers,an exclusionary group distance indicator based on node similarity is proposed.The distance is used to measure the average similarity between the node and all nodes which is more important than the node.And the paper proposes a general node selection algorithm-SNBS.(3)Based on the MKE algorithm and the SNBS algorithm,this paper proposes a hybrid heuristic algorithm for identification of a set of vital nodes which named HHA algorithm.Through experimental analysis,under the all-contact SIR and single-contact SIR models,the HHA algorithm has better performance than the VoteRank and DCC algorithms in all networks under the relative ratio ?.The average value of the maximum increase of ? is more than 3%.And HHA algorithm can be effectively applied to real-world application.Through experimental analysis,The SNBS algorithm can effectively increase the distance between the selected nodes.And when it combines with different vital nodes identification algorithms,the overall effect is better than the top-k selection method.When selecting the identification algorithm,we should priority consider the algorithms that is similar to degree centrality or that based on algorithm of identification of a set of vital nodes.In the all-contact SIR model,the influence of the second-order neighbors can be considered at most when selecting the optimal parameter on similarity calculation,and it can obtain an uniform optimal parameter.if the influence of second-order neighbors is considered at most,you should calculate the optimal parameter on similarity first.This paper does not delve into the combination of node's importance and similarity,also the selection of similarity.Future work should be based on the way that combination of in-depth analysis the importance of node and node similarity,and the selection basis for similarity in the network structure.