I believe that the problem of extracting entities from social data would be an hot research problem. Here they use naive social mining for building basic information which is than combined with machine learning techniques.
Extending the graph tech talk [HQ]
Right-Wingers Always Want To "Execute and Torture" Media - Before the Obama Regime began tapping journalists' phone lines and crushing Wikileaks' ability to accept credit card donations, right wingers traditional...
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