Privacy and Social Capital in Online Social Networks

Abstract

In online social networks (OSNs), individual users have a strong desire to expand their social networks through OSN activities and try to maximize the benefits from the social relationships, called social capital. However, with a large-scale social network, their privacy rights have been significantly intruded by adversarial users that perform social attacks including false / illegal private information dissemination or the use of fake identities. In this work, we study how individual users can expand their social networks by making trustworthy friends while not leaking their private information out to unauthorized parties or social attackers. We adopt the concepts of trust and reputation in order to preserve users' privacy while enhancing their social capital in OSNs. Given a social network topology from the Facebook, we model an individual user's interactions with other users based on feeding (e.g., posting information) and feedback behaviors (e.g., providing likes or comments). Our results show that there exists a tradeoff between social capital and privacy preservation. In addition, we show there exists a balance point of social capital and privacy thresholds that maximizes correct information diffusion while minimizing illegal private information leakout, given users' risk appetite for preserving privacy.