Abstract-The paper presents Visual-VM, a social network visualization tool, where the main focus is to provide utilities for viral marketing (e.g., influence maximization). Besides, Visual-VM utilizes the location information of each user (which could be estimated from the user's profile) for social network visualization, which is not used in existing social network visualization tools. Visual-VM also supports common utilities for social network exploration.
Keywords-Social network visualization, viral marketingI. INTRODUCTION Viral marketing [1][2][3][4] is an advertising strategy which utilizes the "word-of-mouth" effect among the friends in social networks. Specifically, instead of covering massive users directly as traditional advertising methods do, viral marketing targets a limited number of initial users (e.g., by providing incentives) and utilizes their social relationships, such as friends, families and co-workers, to further spread the awareness of the product among individuals. Each individual who gets the awareness of the product is said to be influenced. The number of all influenced individuals corresponds to the influence incurred by the initial users.The propagation process of viral marketing within a social network can be described as follows. At the beginning, the advertiser targets a set of initial users, e.g., by providing some incentives, which we call seeds. Then, the seeds initiate the diffusion process of the product information in the social network. Many models studying how the above diffusion process works have been proposed. Among them, the Independent Cascade Model (IC model) [5] and the Linear Threshold Model (LT model) [6] are the two widely-used models.As mentioned above, in a viral marketing campaign, a company (advertiser) first targets a limited number of seeds and then these seeds would initiate the diffusion process of the product information in the social network. Thus, the most critical issue for viral marketing is to decide which users should be targeted as seeds at the beginning.To answer this question, existing studies on viral marketing mainly consider the following two scenarios.• The budget of how many seeds could be targeted is given, e.g., , and the goal is to maximize the influence resulted from the diffusion process initiated by the seeds. The seed selection problem in this scenario is called influence maximization [1,2].• The influence requirement has been specified, e.g., at least users should be influenced, and the goal is to minimize