Reidentifying Anonymous Data

Latanya Sweeney has demonstrated how easy it can be to identify people from their birth date, gender, and zip code. The anonymous data she reidentified happened to be DNA data, but that's not relevant to her methods or results.

Of the 1,130 volunteers Sweeney and her team reviewed, about 579 provided zip code, date of birth and gender, the three key pieces of information she needs to identify anonymous people combined with information from voter rolls or other public records. Of these, Sweeney succeeded in naming 241, or 42% of the total. The Personal Genome Project confirmed that 97% of the names matched those in its database if nicknames and first name variations were included.

Her results are described here.