--- abstract: "Online Social Networks (OSNs) are a unique Web and social phenomenon, affecting tastes and behaviors of their users and helping them to maintain/create friendships. It is interesting to analyze the growth and evolution of Online Social Networks both from the point of view of marketing and other of new services and from a scientific viewpoint, since their structure and evolution may share similarities with real-life social networks. In social sciences, several techniques for analyzing (online) social networks have been developed, to evaluate quantitative properties (e.g., defining metrics and measures of structural characteristics of the networks) or qualitative aspects (e.g., studying the attachment model for the network evolution, the binary trust relationships, and the link prediction problem).\r\nHowever, OSN analysis poses novel challenges both to Computer and Social scientists. We present our long-term research effort in analyzing Facebook, the largest and arguably most successful OSN today: it gathers more than 500 million users. Access to data about Facebook users and their friendship relations, is restricted; thus, we acquired the necessary information directly from the front-end of the Web site, in order to reconstruct a sub-graph representing anonymous interconnections among a significant subset of users. We describe our ad-hoc, privacy-compliant crawler for Facebook data extraction. To minimize bias, we adopt two different graph mining techniques: breadth-first search (BFS) and rejection sampling. To analyze the structural properties of samples consisting of millions of nodes, we developed a specific tool for analyzing quantitative and qualitative properties of social networks, adopting and improving existing Social Network Analysis (SNA) techniques and algorithms." altloc: [] chapter: ~ commentary: ~ commref: ~ confdates: ~ conference: ~ confloc: ~ contact_email: ~ creators_id: [] creators_name: - family: Catanese given: Salvatore honourific: '' lineage: '' - family: De Meo given: Pasquale honourific: '' lineage: '' - family: Ferrara given: Emilio honourific: '' lineage: '' - family: Fiumara given: Giacomo honourific: '' lineage: '' - family: Provetti given: Alessandro honourific: '' lineage: '' date: 2011 date_type: completed datestamp: 2011-10-27 01:34:27 department: ~ dir: disk0/00/00/76/68 edit_lock_since: ~ edit_lock_until: 0 edit_lock_user: ~ editors_id: [] editors_name: [] eprint_status: archive eprintid: 7668 fileinfo: application/pdf;http://cogprints.org/7668/1/SN%2D76.pdf full_text_status: public importid: ~ institution: ~ isbn: ~ ispublished: pub issn: ~ item_issues_comment: [] item_issues_count: ~ item_issues_description: [] item_issues_id: [] item_issues_reported_by: [] item_issues_resolved_by: [] item_issues_status: [] item_issues_timestamp: [] item_issues_type: [] keywords: ~ lastmod: 2011-10-27 01:34:27 latitude: ~ longitude: ~ metadata_visibility: show note: ~ number: ~ pagerange: ~ pubdom: TRUE publication: 'Computational Social Networks: Mining and Visualization' publisher: 'Springer Verlag, London' refereed: TRUE referencetext: ~ relation_type: [] relation_uri: [] reportno: ~ rev_number: 6 series: ~ source: ~ status_changed: 2011-10-27 01:34:27 subjects: - comp-sci-mach-dynam-sys - comp-sci-mach-learn succeeds: 7633 suggestions: ~ sword_depositor: ~ sword_slug: ~ thesistype: ~ title: Extraction and Analysis of Facebook Friendship Relations type: bookchapter userid: 14714 volume: ~