The amount of personal information posted by users on Facebook has been on the rise despite efforts to protect privacy, according to a seven-year Carnegie Mellon University (CMU) study carried out from 2005 to 2011.
The study, "Silent Listeners: The Evolution of Privacy and Disclosure on Facebook" tracked information from a panel of 5,076 Facebook users and discovered their behaviour on the social network changed over time.
During 2005 to 2009, Facebook users gradually reduced the amount of personal data being shared publicly on the site.
Between 2009 and 2010, the social networking site modified its user interface and default settings, which increased public sharing of personal information.
CMU Information Technology and Public Policy associate professor, Alessandro Acquisti, said that the findings highlight the tension between privacy choices as expressions of individual subjective preferences, and the role of the network environment in shaping those choices.
"While people try to take control of their personal information, the network keeps changing, affecting their decisions and changing their privacy outcomes," Acquisti said.
Eventually, Facebook users increased the amount of information being shared among friends, while also increasing the amount of personal information being shared with 'silent listeners' including third-party apps and advertisers.
CMU researcher, Fred Stutzman, said: "These findings illustrate the challenges social network users face when trying to manage online privacy, the power of social media providers to affect their disclosure and privacy behaviour, and the potential limits of notice and consent mechanisms in addressing consumers' on-line privacy concerns."
CMU researcher, Ralph Gross, said: "Access to settings which help individuals determine which pro?le data other users get to see may increase members' feeling of control, but perceptions of control over personal data and the misdirection of users' attention have been linked to increases in disclosures of sensitive information to strangers."