Heterogeneous Influence Maximization in User Recommendation

GAWF: Influence maximization method based on graph attention weight fusion

Influence Extremal Optimization (InfEO) is an algorithm based on Extremal Optimization, adapted for the influence maximization problem for the independent cascade model. InfEO maximizes the marginal contribution of a node to the influence set of the model. Numerical experiments are used to compare InfEO with other influence maximization methods, indicating the potential of this approach. Practical results are discussed on a network constructed from publication data in the field of computer science.

The process of rumor spreading among people can be represented as information diffusion in social network. The scale of rumor spread changes greatly depending on starting vertices. If we can select vertices that contribute to large scale diffusion, the vertices are expected to be important for viral marketing. Given a network and the size of the starting vertices, the problem of selecting vertices for maximizing information diffusion is called as influence maximization problem. We propose three new approximation methods for influence maximization problem in dynamic networks. These methods are the extensions of previous methods for static networks to dynamic networks. Experiments for comparing the performance show that our proposed method achieves 1.5 times as much in the scale of diffusion and approximately 7.8 times faster in computational time at the maximum compared with previous heuristic methods.

A New Method for Influence Maximization in Social Networks

Pharmacogenomics is the study of how genes affect a person's response to drugs. Thus, understanding the effect of drug at the molecular level can be helpful in both drug discovery and personalized medicine. Over the years, transcriptome data upon drug treatment has been collected and several databases compiled before drug treatment cancer cell multi-omics data with drug sensitivity (IC50, AUC) or time-series transcriptomic data after drug treatment. However, analyzing transcriptome data upon drug treatment is challenging since more than 20,000 genes interact in complex ways. In addition, due to the difficulty of both time-series analysis and multi-omics integration, current methods can hardly perform analysis of databases with different data characteristics. One effective way is to interpret transcriptome data in terms of well-characterized biological pathways. Another way is to leverage state-of-the-art methods for multi-omics data integration. In this paper, we developed Drug Response analysis Integrating Multi-omics and time-series data (DRIM), an integrative multi-omics and time-series data analysis framework that identifies perturbed sub-pathways and regulation mechanisms upon drug treatment. The system takes drug name and cell line identification numbers or user's drug control/treat time-series gene expression data as input. Then, analysis of multi-omics data upon drug treatment is performed in two perspectives. For the multi-omics perspective analysis, IC50-related multi-omics potential mediator genes are determined by embedding multi-omics data to gene-centric vector space using a tensor decomposition method and an autoencoder deep learning model. Then, perturbed pathway analysis of potential mediator genes is performed. For the time-series perspective analysis, time-varying perturbed sub-pathways upon drug treatment are constructed. Additionally, a network involving transcription factors (TFs), multi-omics potential mediator genes, and perturbed sub-pathways is constructed, and paths to perturbed pathways from TFs are determined by an influence maximization method. To demonstrate the utility of our system, we provide analysis results of sub-pathway regulatory mechanisms in breast cancer cell lines of different drug sensitivity. DRIM is available at: http://biohealth.snu.ac.kr/software/DRIM/.

The popularity of social networks has grown manifolds in recent years because of various activities like fast propagation of ideas, publicity, and news. Influence maximization (IM) is one of the most highly studied problems in the field of social network analysis due to its business values. Influence maximization aims to identify influential nodes that can spread the information to the maximum number of nodes in the network through diffusion cascade. Traditional methods for IM include centrality based and greedy based measures. However, each method has some limitations. Recently, some methods of IM are introduced, which consider the presence of community structure in networks. Community structure has a significant impact on information diffusion, because of dense connections between the nodes in the community. In this paper, we propose a novel influence maximization algorithm using node seeding, label propagation, and community detection. We first use extended h-index centrality to detect the seed nodes and then use the label propagation technique to detect communities. Further, we merge smaller and related communities to a larger community with the help of a relationship matrix. Finally, top-k influential nodes from these communities are identified. These ideas lead to our proposed algorithm: Influence Maximization using Extended h-index, and Label Propagation with Relationship matrix (IM-ELPR). We adopt Independent Cascade (IC) information diffusion model to spread the information originating from chosen influential nodes. The proposed algorithm intends to identify influential nodes from different communities globally and does not depend on the specific community’s antecedent structural information. Experimental results performed on several real-life data sets reveal that the proposed algorithm performs better than many other existing popular algorithms.

This paper proposes: a tool for virtual learning platforms that recommends users who know about a particular subject; a new recommender method that takes into account the users' knowledge about a subject and their future availability based on past interactions and a text mining method to obtain user information from forums. A user recommender system was implemented in the Moodle platform to demonstrate the feasibility of the proposal.

SummaryOnline social networks play a pivotal role in the propagation of information and influence as in the form of word‐of‐mouth spreading. The influence maximization (IM) problem is a fundamental problem to identify a small set of individuals, which have a maximal influence spread in the social network. Unfortunately, the IM problem is NP‐hard. It has been depicted that a hill‐climbing greedy approach gives a good approximation guarantee. However, it is inefficient to run on large‐scale social networks. In this paper, a global influence evaluation function is presented for the IM optimization problem. The global influence evaluation function provides a reliable expected diffusion value of influence spread under the traditional diffusion models. To optimize global influence evaluation function, an influence maximization algorithm based on social spider optimization (IM‐SSO) is presented. IM‐SSO redefines the representation and update rule of spider's vibration and performs random walk towards target vibration. The algorithm uses a jump away process to overcome the weakness of premature convergence. The experimental results on six real‐world social networks show that the proposed algorithm is more effective than the state‐of‐the‐art heuristics and more time‐efficient than CELF++, static greedy, and PSO with an approximate influence spread.

The connection between users in social networks can be maintained for a certain period of time, and the static network structure formed provides the basic conditions for various kinds of research, especially for discovering customer groups that can generate great influence, which is important for product promotion, epidemic prevention and control, and public opinion supervision, etc. However, the computational process of influence maximization ignores the timeliness of interaction behaviors among users, the screened target users cannot diffuse information well, and the time complexity of relying on greedy rules to handle the influence maximization problem is high. Therefore, this paper analyzes the influence of the interaction between nodes in dynamic social networks on information dissemination, extends the classical independent cascade model to a dynamic social network dissemination model based on effective links, and proposes a two-stage influence maximization solution algorithm (Outdegree Effective Link—OEL) based on node degree and effective links to enhance the efficiency of problem solving. In order to verify the effectiveness of the algorithm, five typical influence maximization methods are compared and analyzed on four real data sets. The results show that the OEL algorithm has good performance in propagation range and running time.

The influence maximization (IM) is an optimization problem in the information propagation and social network analysis, which has the goal of finding a seed set that can influence largest number of users. There have been many studies on the IM problem, but most of them focus on maximizing influence effects based on individuals rather than on groups of users. In this paper, we studied a novel problem, the Threshold Benefit for Groups Influence (named \({\mathsf {TGI}}\)), defined as follows: given a social network G, a set of K target groups \({\mathcal C} =\{C_1, C_2, \ldots , C_K\}\) and a threshold \(T>0\), \({\mathsf {TGI}}\) asks us to find a seed set S in G with the minimum cost so that the benefit gained from the influence of the groups in C is at least T. We experimentally implement our proposed algorithm on real social network datasets diversity. It shows efficiency compared to other state-of-the-art IM algorithms in terms of cost and running time.

SummaryTraffic bottlenecks dynamically change with the variance of traffic demand. Identifying traffic bottlenecks plays an important role in traffic planning and provides decision making. However, traffic bottlenecks are difficult to identify because of the complexity of traffic road networks and many other factors. In this article, we propose an influence spreading based method to find the dynamic changed traffic bottlenecks, where the influence caused by bottlenecks is maximal. We first build a traffic congestion diffusion (TCD) model to capture traffic flow influence (TFI) spreading over traffic road networks. The bottlenecks identification problem based on TCD is modeled as an influence maximization problem, that is, selecting the most influential nodes such that the deterioration of traffic condition is maximal. With the proof of the submodularity of TFI spreading over traffic networks, a provably near‐optimal algorithm is used to solve the NP‐hard problem. With the exploration of unique properties of TFI spread, an approximate influence maximization method for TCD (TCD‐AIM) is proposed. To the best of our knowledge, this should be the first model for a metro‐city scale from the influence perspective. Experimental results show that TCD‐AIM finds bottlenecks with up to 130% congestion density increase in the future.

Influence maximization (IM) in dynamic social networks is an optimization problem to analyze the changes in social networks for different periods. However, the existing IM methods ignore the context propagation of interaction behaviors among users. Hence, context-based IM in multiplex networks is proposed here. Initially, multiplex networks along with their contextual data are taken as input. Community detection is performed for the network using the Wilcoxon Hypothesized K-Means (WH-KMA) algorithm. From the detected communities, the homogeneous network is used for extracting network topological features, and the heterogeneous networks are used for influence path analysis based on which the node connections are weighted. Then, the influence-path-based features along with contextual features are extracted. These extracted features are given for the link prediction model using the Parametric Probability Theory-based Long Short-Term Memory (PPT-LSTM) model. Finally, from the network graph, the most influencing nodes are identified using the Linear Scaling based Clique (LS-Clique) detection algorithm. The experimental outcomes reveal that the proposed model achieves an enhanced performance.

Most online discussion interfaces organize textual responses using linear lists. Such lists do not scale to the number of responses and cannot convey the diversity of the participants who have contributed. The Opinion Space system is designed to address these issues. In this paper, we augment Opinion Space with two features. The first is a new user interface tool and recommendation system: the Diversity Donut (Figure 1). While the Diversity Donut did not establish a statistical advantage over other recommendation methods, participant self-reported data suggested that participants found the Diversity Donut to yield the most diverse set of comments. The second contribution is a new dimensionality reduction technique in Opinion Space: Canonical Correlation Analysis (CCA). Our analysis suggests that CCA is a better algorithm for opinion visualization than Principal Component Analysis (PCA).

The problem of influence maximization aims to specify the small number of initial individuals that will eventually influence the individuals as much as possible, which has aroused wide attention of researchers. However, the most existing work is limited to the static social network and ignores the role of time in information propagation. In this paper, we analyze the influence maximization problem in temporal social networks and present a greedy-based on the latency-aware independent cascade (GLAIC) algorithm enhanced by cost-effective lazy forward optimization based on the latency-aware independent cascade model to capture the dynamic aspect of real-world social networks. Moreover, we modify the distribution of influence delays in the LAIC model by considering power-law distribution. At last, we carry out extensive experiments over the real-world networks, which demonstrate that our proposal achieves an excellent performance to other related algorithms.

Microblogging networks have gained popularity in recent years as a platform enabling expressions of human emotions, through which users can conveniently produce contents on public events, breaking news, and/or products. Subsequently, microblogging networks generate massive amounts of data that carry opinions and mass sentiment on various topics. Herein, microblogging is regarded as a useful platform for detecting and propagating new hot events. It is also a useful channel for identifying high-quality posts, popular topics, key interests, and high-influence users. The existence of noisy data in the traditional social media data streams enforces to focus on human-centric computing. This paper proposes a human-centric social computing (HCSC) model for hot-event detection and propagation in microblogging networks. In the proposed HCSC model, all posts and users are preprocessed through hypertext induced topic search (HITS) for determining high-quality subsets of the users, topics, and posts. Then, a latent Dirichlet allocation (LDA)-based multiprototype user topic detection method is used for identifying users with high influence in the network. Furthermore, an influence maximization is used for final determination of influential users based on the user subsets. Finally, the users mined by influence maximization process are generated as the influential user sets for specific topics. Experimental results prove the superiority of our HCSC model against similar models of hot-event detection and information propagation.