In this paper, we address the problem of revenue maximization (RM) for multi-grade products in social networks by considering pricing, seed selection, and coupon distribution. Previous works on RM often focus on a single product and neglect the use of coupons for promotion. We propose a new optimization problem,Revenue Maximization of Multi-Grade Product(RMMGP), to simultaneously determine pricing, seed selection, and coupon distribution for multi-grade products with both promotional and competitive relationships between grades in order to maximize revenue through viral marketing. We prove the hardness and inapproximability of RMMGP and show that the revenue function is not monotone or submodular. To solve RMMGP, we design an approximation algorithm, namelyData-Dependent Revenue Maximization (DDRM), and propose thePricing-Seeding-Coupon allocation (PriSCa)algorithm, which uses the concepts of Worth Receiving Probability, Pricing-Promotion Alternating Framework, and Independent/Holistic Customer-Grade Determinant sets. Our experiments on real social networks, using valuation distributions from Amazon.com, demonstrate that PriSCa and DDRM achieve on average 1.5 times higher revenue than state-of-the-art approaches. Additionally, PriSCa is efficient and scalable on large datasets.

Viral marketing on social networks, also known as Influence Maximization (IM), aims to select k users for the promotion of a target item by maximizing the total spread of their influence. However, most previous works on IM do not explore the dynamic user perception of promoted items in the process. In this paper, by exploiting the knowledge graph (KG) to capture dynamic user perception, we formulate the problem of Influence Maximization based on Dynamic Personal Perception (IMDPP) that considers user preferences and social influence reflecting the impact of relevant item adoptions. We prove the hardness of IMDPP and design an approximation algorithm, named Dynamic perception for seeding in target markets (Dysim), by exploring the concepts of dynamic reachability, target markets, and substantial influence to select and promote a sequence of relevant items. We evaluate the performance of Dysim in comparison with the state-of-the-art approaches using real social networks with real KGs. The experimental results show that Dysim effectively achieves at least 6 times of influence spread in large datasets over the state-of-the-art approaches.

Existing research on social networks manifests two crucial criteria to improve activity engagement of users: (1) user interests in the activity topics and (2) opportunities of making new friends with some acquaintances. However, current online platforms still involve massive manual selection for activity attendees and contents without proper recommendations. In this paper, therefore, we formulate a new activity organization problem, named Social Knowledge Group Query (SKGQ), to recommend attendees and topic-related contents simultaneously. We prove that SKGQ is NP-hard and design an approximation algorithm, named Social cOntent Knowledge Exploration (SOKE), to jointly choose the activity attendees and topic-related contents according to social-oriented and topic- oriented strategies. Simulation results manifest that the solution acquired by SOKE is close to the optimal solution and outperforms various baselines.

The problem of revenue maximization, which aims at earning the highest revenue by properly pricing the product and/or seeding customers, is an important issue about utilizing the social influences. In this paper, we are interested in the marketing of the multi-grade product, where the different grades of a product from a company, such as iPhone 8, iPhone 8 Plus, and iPhone X, have both competitive and promotional relationships. For the study, a new diffusion model named MuG-IC (Multi-Grade IC) is first proposed based on the IC and the concave graph models to describe the phenomena of social influences regarding the multi-grade product. Afterwards, we then study the revenue maximization upon the MuG-IC and solve the problem by designing a novel algorithm named PS (Pricing-Seeding). The PS algorithm can give proper suggestions of pricing each grade of the product and seeding customers by tuning the suggestions in an iterative manner. The experiments conducted on the real network structure with simulated valuation distributions from Amazon.com demonstrate the effectiveness of the proposed algorithm.

Privacy for mobile devices will be more and more important, while data in the devices are easily be hacked. Traditional mobile unlocking systems such as inner password unlock and graphics unlock are unsecure so that this study is based on fingerprint with touch identify and Advanced Encryption Standard (AES) to effectively secure mobile privacy data and to reduce the risk of data leaking.

Online posts not only represent the records of people's lives but also reveal their satisfaction with life and relationships as well as potential mental illnesses. The detection of (strong or general) negative as well as (strong or general) positive feelings of people from online posts can keep us from carelessly missing their important moments, difficult or great, due to the overloaded information in the daily life and lead to a better society. Therefore, in this paper, we build a Feeling Distinguisher system based on supervised Latent Dirichlet Allocation (sLDA), Latent Dirichlet Allocation, and SentiWordNet methodologies for detecting a person's intention and intensity of feelings through the analysis of his/her online posts. Experimental results on posts collected from five social network websites demonstrate the effectiveness of FeD. The performance of FeD is about 1.08-1.18 folds that of SVM and sLDA.

As the social networking websites arise, the social network has become an important vehicle for sharing information and exerting influences. For the widespread utilization of social influences, a lot of works such as influence maximization and innovation promotion have been studied on various diffusion models. However, to the best of our knowledge, none of the existing works has incorporated the interplay between the intensity of interest and influence strength, which has been widely observed in social sciences, into the diffusion model. To fulfill this gap, in this paper, we propose the ID model that is able to capture the dynamic influence strength owing to the interplay. Under this ID model, we address the novel utilization of dynamic influence strength for personalized promotion to grow the intensity of a target individual's interest in an issue. In particular, to have the cost of promotion minimized, we introduce a novel Algorithm ISES to search for the least number of individuals as seeds in the promotion strategy. The ISES algorithm is able to identify the cost-effective solution by adopting the backtracking search and employing pruning strategies. On the real dataset of DBLP, the experiments demonstrate the effectiveness of ISES.

Recently the influence maximization problem has received much attention for its applications on viral marketing and product promotions. However, such influence maximization problems have not taken into account the monetary effect on the purchasing decision of individuals. To fulfill this gap, in this paper, we aim for maximizing the revenue by considering the quantity constraint on the promoted commodity. For this problem, we not only identify a proper small group of individuals as seeds for promotion but also determine the pricing of the commodity. To tackle the revenue maximization problem, we first introduce a strategic searching algorithm, referred to as Algorithm PRUB, which is able to derive the optimal solutions. After that, we further modify PRUB to propose a heuristic, Algorithm PRUB+IF, for obtaining feasible solutions more efficiently on larger instances. Experiments on real social networks with different valuation distributions demonstrate the effectiveness of PRUB and PRUB+IF.

Recently, health-care has become a popular issue. Having a good physique is also commonly regarded as important for being healthy. For evaluating our body status, the Body Mass Index (BMI) is a widely used indicator. However, calculating BMI is inconvenient and requires the physical measuring of people's weights and heights. In this paper, we are interested in building a mobile-based BMI prediction system using Kinect and data mining techniques so that everybody can easily monitor their BMI everywhere by taking a snapshot of their face. The rationale behind this is the intuition that there is a correlation between the shape of one's face and one's BMI values, which people often act on when noticing a friend has either gained or lost weight. Through the evaluations of 50 volunteers, we show that the rules for training BMI prediction match with people's common intuitions.

Due to the emergence of social platforms, people tend to posting their diaries and feeling online for sharing with others. In this paper, we aim to predict whether a user is getting depressed or not through his blog posts on the Internet. For this purpose, we use Latent Dirichlet Allocation (LDA) to find out top frequency words appearing in a user's diaries and use SentiWordNet to calculate the emotion score of the user. Experimental results show that our method is useful in the diagnosis of mental disorder detection in social platforms.

With the advances of information technology, there are increasing researches aiming at assisting depression diagnosis and treatment. In most of them the user is necessarily actively joining the diagnosis and treatment program while he has perceived mental disorder himself. In order to early prevent the mental disorder, in this paper we propose an early warning mechanism that observes and mines user diary published on social network platform, and generates a score of getting mental disordered or depressed. If the score is large than a threshold, the system can notify the user and his friends on the social network to take care about the friend. We have conducted experiments to evaluate the proposed approach, and the results show that the proposed approach is effective.

Social networks model the social activities between individuals, which change as time goes by. In light of useful information from such dynamic networks, there is a continuous demand for privacy-preserving data sharing with analyzers, collaborators or customers. In this paper, we address the privacy risks of identity disclosures in sequential releases of a dynamic network. To prevent privacy breaches, we proposed novel kw-structural diversity anonymity, where k is an appreciated privacy level and w is a time period that an adversary can monitor a victim to collect the attack knowledge. We also present a heuristic algorithm for generating releases satisfying kw-structural diversity anonymity so that the adversary cannot utilize his knowledge to reidentify the victim and take advantages. The evaluations on both real and synthetic data sets show that the proposed algorithm can retain much of the characteristics of the networks while confirming the privacy protection.

As an increasing number of social networking data is published and shared for commercial and research purposes, privacy issues about the individuals in social networks have become serious concerns. Vertex identification, which identifies a particular user from a network based on background knowledge such as vertex degree, is one of the most important problems that have been addressed. In reality, however, each individual in a social network is inclined to be associated with not only a vertex identity but also a community identity, which can represent the personal privacy information sensitive to the public, such as political party affiliation. This paper first addresses the new privacy issue, referred to as community identification, by showing that the community identity of a victim can still be inferred even though the social network is protected by existing anonymity schemes. For this problem, we then propose the concept of structural diversity to provide the anonymity of the community identities. The k-Structural Diversity Anonymization (k-SDA) is to ensure sufficient vertices with the same vertex degree in at least k communities in a social network. We propose an Integer Programming formulation to find optimal solutions to k-SDA and also devise scalable heuristics to solve large-scale instances of k-SDA from different perspectives. The performance studies on real data sets from various perspectives demonstrate the practical utility of the proposed privacy scheme and our anonymization approaches.

Information network analysis has drawn a lot attention in recent years. Among all the aspects of network analysis, similarity measure of nodes has been shown useful in many applications, such as clustering, link prediction and community identification, to name a few. As linkage data in a large network is inherently sparse, it is noted that collecting more data can improve the quality of similarity measure. This gives different parties a motivation to cooperate. In this paper, we address the problem of link-based similarity measure of nodes in an information network distributed over different parties. Concerning the data privacy, we propose a privacy-preserving Sim Rank protocol based on fully-homomorphic encryption to provide cryptographic protection for the links.

Privacy in social network data publishing is always an important concern. Nowadays most prior privacy protection techniques focus on static social networks. However, there are additional privacy disclosures in dynamic social networks due to the sequential publications. In this paper, we first show that the risks of vertex and community re-identification exist in a dynamic social network, even if the release at each time instance is protected by a static anonymity scheme. To prevent vertex and community re-identification in a dynamic social network, we propose novel dynamic kw-structural diversity anonymity, where w is the time that an adversary can monitor a victim. This scheme extends the k-structural diversity anonymity to a dynamic scenario. We also present a heuristic to anonymize the releases of networks to satisfy the proposed privacy scheme. The evaluations show that our approach can retain much of the characteristics of the networks while confirming the privacy protection.

Due to the rich information in graph data, the technique for privacy protection in published social networks is still in its infancy, as compared to the protection in relational databases. In this paper we identify a new type of attack called a friendship attack. In a friendship attack, an adversary utilizes the degrees of two vertices connected by an edge to re-identify related victims in a published social network data set. To protect against such attacks, we introduce the concept of k2-degree anonymity, which limits the probability of a vertex being re-identified to 1/k. For the k2-degree anonymization problem, we propose an Integer Programming formulation to find optimal solutions in small-scale networks. We also present an efficient heuristic approach for anonymizing large-scale social networks against friendship attacks. The experimental results demonstrate that the proposed approaches can preserve much of the characteristics of social networks.

How to protect individual privacy in public data is always a concern. For social networks, the challenge is that, the structure of the social network graph can be utilized to infer the private and sensitive information of users. The existing anonymity schemes mostly focus on the anonymity of vertex identities, such that a malicious attacker cannot associate an user with a specific vertex. In real social networks, however, each vertex is usually associated with not only a vertex identity but also a community identity, which could represent the private information for the corresponding user, such as the political party affiliation or disease information sensitive to the public. In this paper, we first show that the attacker can still infer the community identity of an user even though the graph is protected by previous anonymity schemes. Afterward, we propose the structural diversity, which ensures the existences of at least k communities containing vertices with the same degree for every vertex in the graph, to provide the anonymity of the community identities. Specifically, we formulate a new problem, k-Structural Diversity Anonymization (k-SDA), which protects the community identity of each individual in publishing social networks. We propose an Integer Programming formulation to find the optimal solutions to k-SDA. Moreover, we devise three scalable heuristics to solve the large instances of k-SDA with different perspectives. The experiments on real data sets demonstrate the practical utility of our privacy model and our approaches.

For any outsourcing service, privacy is a major concern. This paper focuses on outsourcing frequent itemset mining and examines the issue on how to protect privacy against the case where the attackers have precise knowledge on the supports of some items. We propose a new approach referred to as k-support anonymity to protect each sensitive item with k-1 other items of similar support. To achieve k-support anonymity, we introduce a pseudo taxonomy tree and have the third party mine the generalized frequent itemsets under the corresponding generalized association rules instead of association rules. The pseudo taxonomy is a construct to facilitate hiding of the original items, where each original item can map to either a leaf node or an internal node in the taxonomy tree. The rationale for this approach is that with a taxonomy tree, the k nodes to satisfy the k-support anonymity may be any k nodes in the taxonomy tree with the appropriate supports. So this approach can provide more candidates for k-support anonymity with limited fake items as only the leaf nodes, not the internal nodes, of the taxonomy tree need to appear in the transactions. Otherwise for the association rule mining, the k nodes to satisfy the k-support anonymity have to correspond to the leaf nodes in the taxonomy tree. This is far more restricted. The challenge is thus on how to generate the pseudo taxonomy tree to facilitate k-support anonymity and to ensure the conservation of original frequent itemsets. The experimental results showed that our methods of k-support anonymity can achieve very good privacy protection with moderate storage overhead.

Applications with geo-tagged photos have drawn lots of attentions in recent years. However, most previous works consider the GPS information of each photo individually to improve the metadata of the corresponding photo. In this paper, we leverage GPS data in a series of scenic photos and propose the personalized scenic itinerary recommendation system. Our system provides personalized suggestion of a sequence of following visiting spots when each user takes the photo of the current scenic spot. The recommendation is based on the data mining techniques to extract and differentiate the preferences of various users. Our system is designed to provide a new location service for geo-tagged photo management.