News websites and apps will ask readers to sign in with their Facebook accounts so that they can send info to the social network about every article they read.
It's been quite some time since the new privacy policy was introduced, but the university says the sample group didn't reduce the amount of info shared with non-friends on the network, even as of 2011.
Blogger and search marketer Tamar Weinberg suggested that users provided contact info with their Digg accounts, encouraging other users to contact them and thus building a network that can be used to float links higher on the site.