ABSTRACT
Many social, biological, and information systems can be naturally described as networks, where vertices represent entities and links denote relations or interactions. Social network consists of individuals and their relations such as friendship and partnership. In the field of sociology, there has been a long history of social network analysis which investigates the relations among social entities. In recent years, social network analysis has attracted considerable attention from various business perspectives, such as marketing and business process modeling. In social networks, links among entities may vary dynamically. For example, email communications and cooperative interactions are changing over time.
