
109Developments and Challenges in Location Mining
We make several interesting observations that distinguish Twitter from other OSNs like Facebook
and LiveJournal:
• A link from A to B (A following B) does not always mean there is an edge from B to A (B
follows A back).
• A link from A to B (A following B), unlike Facebook or LinkedIn, does not always indicate
friendship, but sometimes means that A is interested in the messages posted by B.
• If A has a public prole (which is true for a large majority of proles), then he or she has
little control over who follows him or her.
• Twitter is a popular OSN used by celebrities (large follower-to-fo ...