Too Long; Didn't Read
In this post, we will look at some examples of reconstruction attacks, i.e., how one can reveal the most sensitive information about individuals from seemingly anonymous data. An example of how things might go wrong with aggregate statistics is revealing an average salary of 100 employees and then publishing an average of 101 after a new employee has joined. The task is even easier for an attacker who cleverly uses non-uniform sampling e.g., by exploiting the fact that calls from an office at 2 am might provide more information about an individual than calls at 3 pm when the office is crowded.