bridging social capital, happiness, satisfaction with life, loneliness, depression, positive affect, negative affect,

Social network sites count millions of members these days. For a growing number of Internet users, maintaining a profile on a social network site is part of their everyday life today. The debate of the social use of the Internet has focused on the one hand, on whether persons establish new relationships online and, on the other hand, on how persons use the Internet to maintain relationships. Social network sites explicitly aim at supporting people in both aspects. The number of members shows their success, but do social network sites really afford the maintenance of existing and establishment of new contacts? As yet, there has been no systematic investigation of the motivations and usage patterns on social network sites. This study lays the groundwork describing the social networks displayed as well as the perceptions members have of the displayed connections between others. Furthermore, the frequency, motivations and outcome of the creation of links to yet unknown persons are investigated. Participants of a German SNS were surveyed with an online questionnaire. The results show rather small networks which consist of both work and private contacts suggesting a substantial overlap with the offline networks. Regarding new links, over half of the users have added an as yet unknown person to their contact list, but many of new relationships do not develop further.

In the past, most researchers focused on the efficacy of tie-strength in various applications for both online and offline social networks. However, how tie-strength can help in the analysis of online social networks was a commonly neglected issue. The massive size and recording properties of online social networks offer the possibility to measure tie-strength objectively. In this study, we examine a social network extracted from a blog network. We then propose a tie-strength measurement and investigate several properties of the network using the tie-strength we defined. We also study how tie-strength