An interesting news item on how social security numbers can be guessed with surprising accuracy made this morning’s paper. Researchers say they can determine much of someone’s social security number from birth date and location. Hopefully this will shine yet another spotlight on our over-reliance on social security numbers as a method of identification. From the San Jose Mercury news:

For people born after 1988 – when the government began issuing numbers at birth – the researchers were able to identify, in a single attempt, the first five Social Security digits for 44 percent of individuals. And they got all nine digits for 8.5 percent of those people in fewer than 1,000 attempts.

The predictability of the numbers increases the risk of identity theft, which cost Americans almost $50 billion in 2007 alone, Acquisti said.

That is fairly accurate, all things considered. When researchers Alessandro Acquisti and Ralph Gross make their research public, just as with most efforts of this type, we will see the research community at large make improvements in the methodology and accuracy of results. And in the long run, who says that the ‘guesser’ only gets one try?

What made me crack up in this news report was the Social Security Administration’s Mark Lassiter’s response that “… there is no foolproof method for predicting a person’s Social Security number,” and his statement that “The public should not be alarmed …”. Identity thieves and criminals don’t need 100% accuracy; a few million legitimate numbers ought to be sufficient.