While many users feel their personal data is safe on social networking sites because they have set high levels of security settings, research suggests this is not the case. According to a 2010 Northeastern University and Max Planck Institute for Software Systems study, researchers created an algorithm to discover an individual's personal attributes by examining the one thing that most people leave public even when all other privacy settings are place: their friend list. Using the algorithm, researchers were able to infer many personal traits merely from friend lists, including educational level, university attended, hometown and other private data.