Slashdot Mirror
A Wrinkle For Biometric Systems: Irises Change Over Time
scibri writes "The iris scanners that are used to police immigration in some countries, like the UK, are based on the premise that your irises don't change over your lifetime. But it seems that assumption is wrong. Researchers from the University of Notre Dame have found that irises do indeed change over time, enough so that the failure rate jumps by 153% over three years. While that means a rise from just 1 in 2 million to 2.5 in two million, imagine how that will affect a system like India's — which already has 200 million people enrolled — over 10 years."
if you were fucking over 0.0000005 of your population already to no significant protest, why would anyone care if you are now fucking over 0.00000125 of your population?
any statistical system should serve only as a first alert; and any positive found thereby should be carefully evaluated by more thorough and human measures.
"They were pure niggers." – Noam Chomsky
One in a million instead of one in two millions. I guess it would still not overload the average office clerk to double check that many people. Yes, it would be a nuisance, but a minor one.
Don't get me wrong, I'm not really a fan of biometrics, but I guess we'd have to come up with a better reason than one of statistical insignificance. Likewise you could say inoculations are bad because one in a million develops a rash so let's toss it altogether.
The only thing that I can take from this is that officials should be informed that a negative on a biometric scan is NOT necessarily a proof that the person is not who he claims to be.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
For the simple reason that many people might find that sort of thing stinks of Big Brother. People are used to official photographs now but generally find other forms of identification such as fingerprinting to be too associated with law enforcement to be acceptable. The appeal of Iris scans would be to do them when children are born and can't protest, meanwhile the parents are probably too overjoyed and tired to protest either.
Also I suspect the authorities don't like biometrics which change because they like to push through cases on forensic identification and so don't like the public thinking about the false positive rate.
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CINC, 4th Penguin Legion
Why not simply use a database to store the scan, and to compare the current scan, and replace with the current scan if it is considered a match? Then the issue is gone. Replaced by other IT issues, I suppose. But still...
Unless you are going 6 months without being scanned, and assuming these changes are fairly linearly progressive and not abrupt, it wouldn't be hard to just update the database with the changes based on an allowed variation over time if multiple scanners are registering a change.
If there is anything wrong with biometric scanning it isn't this.
Iris scanning is NOT used to police immigration in the UK. It was a failed experiment and people are no longer able to register their eyes. Any idiot passing through immigration at Heathrow or Gatwick could see it was taking the biometric people longer, even though there was no queue.
Non sequitur. Just because the iris changes doesn't say it tells you something about your health status. The planets indeed move, does that validate astrology?
The Tao of math: The numbers you can count are not the real numbers.
The tolerance is already set so loose that it only fails to approve the person 1 in 1 million times. It isn't the error rate, it's a reflection of the *wide* error tolerances set.
They did the same trick with the facial scanners, they rejected too many people when trialed at UK airports, so they 'recalibrated' them until they rejected only an acceptable number of people. Where 'recalibrate' is really just increasing the error margin till the reject rate is low enough that the last labour government can justify the purchase price.
Here they've set the iris scanner to only reject 1 in a million, and now it has to be set 3 times looser to reject 1/3rd of 1 in a million in order to keep the reject rate low enough so that it will still be that low after 3 years.
Oh, and one little side effect of these biometrics is that now have to get our passports updated every 5 years instead of 10, making any cost saving at the expense of the passport holder.
And yet iris and retena scans are FAR more privacy friendly than fingerprints or DNA.
We don't go around leaving our eye prints all over the place. And it is far more difficult to obtain them clandestinely.
Guess our bodies are just complying with the company rules to periodically change our passwords.