Is more always merrier?: a deep dive into online social footprints

International audienceWe present an empirical study of personal information revealed in public profiles of people who use multiple Online Social Networks (OSNs). This study aims to examine how users reveal their personal information across multiple OSNs. We first consider the number of publicly available attributes in public profiles, based on various demographics and show a correlation between the amount of information revealed in OSN profiles and specific occupations and the use of pseudonyms. Then, we measure the complementarity of information across OSNs and contrast it with our observations about users who share a larger amount of information. We also measure the consistency of information revelation patterns across OSNs, finding that users have preferred patterns when revealing information across OSNs. To evaluate the quality of aggregated profiles we introduce a consistency measure for attribute values, and show that aggregation also improves information granularity. Finally, taking Australian phone directory as a case study, we demonstrate how the availability of multiple OSN profiles can be exploited to improve the success of obtaining users' detailed contact information, by cross-linking with publicly available data sources such as online phone directories