hide
Free keywords:
-
Abstract:
Online social networking sites like Orkut, YouTube, and Flickr are among the
most popular sites on the Internet. Users of these sites form a social network,
which provides a powerful means of sharing, organizing, and finding content and
contacts. The popularity of these sites provides an opportunity to study the
characteristics of online social network graphs at large scale. Understanding
these graphs is important, both to improve current systems and to design new
applications of online social networks.
This paper presents a large-scale measurement study and analysis of the
structure of multiple online social networks. We examine data gathered from
four popular online social networks: Flickr, YouTube, LiveJournal, and Orkut.
We crawled the publicly accessible user links on each site, obtaining a large
portion of each social network’s graph. Our data set contains over 11.3 million
users and 328 million links. We believe that this is the first study to examine
multiple online social networks at scale.
Our results confirm the power-law, small-world, and scale-free properties of
online social networks. We observe that the indegree of user nodes tends to
match the outdegree; that the networks contain a densely connected core of
high-degree nodes; and that this core links small groups of strongly clustered,
low-degree nodes at the fringes of the network. Finally, we discuss the
implications of these structural properties for the design of social network
based systems.