Making Privacy Protection Investment Decisions in Social Networks: An Interdependent Security Game Approach

Abstract

With the proliferation of users’ sharing behaviors in social networks, the issue of privacy protection has become a major concern of researchers. Most social network platforms provide basic privacy protection mechanisms for users, allowing them to complete privacy settings according to their needs. Each user’s setting can be regarded as a kind of security investment, with different benefits and costs depending on its degree. Due to connections and interactions, users’ investments in privacy protection are interdependent, i.e., users can benefit from their neighbors’ security investments. However, most studies focus on users’ own security investments and ignore their interdependence. Therefore, an interdependent security game approach is proposed to make optimal privacy protection investment decisions for users. This approach first calculates the influence matrix based on users’ interdependence, then constructs the interdependent security game model, and finally solves the Nash equilibrium of this game to derive the optimal investment decisions. The existence and uniqueness of Nash equilibrium are proved, and an iterative method is adopted to calculate the Nash equilibrium solution. The experiments evaluate the interdependent security game model and the iterative method. This work helps each user make accurate investment decision under the influencer of other users on privacy protection, and avoid the over-investment resulting in the waste of resources.