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False Positives, Few Matches Plague 'No-Fly' List
lindner writes "According to a recent article in the San Francisco Chronicle, the United States No-Fly List uses a soundex algorithm to match names. Designed 'to quickly summon passenger names or to catch deal-hunting passengers making duplicate bookings.' The system has only managed to rack up a slew of false-positives, including everyone matching soundex ("J. Adams") at one point in time. The problem has gotten so bad that there is now a "Fly List" for chronically misidentified passengers."
I understand that the airline industry is a little tight right now, but that's just insane.
Unfortunately, the officials implementing a system such as this are going to get crucified either way. If they let a known terrorist onto a plane and a terrorist act happens, their heads are going to roll. Every journalist will be screaming that, "this terrorist has been on the FBI watch list for 2 years, a simple misspelling of his name allowed him to foil the multi-million dolar no fly system".
On the other hand, false positives are going to make the system useless as the boy who cried wolf one too many times found out. There doesn't seem to be an easy solution to this problem.
The more you know, the less you understand.
It should be obvious to anyone that any mechanism designed to target a small group out of a large group will would have to have an extremely small false positive rate to be of any use.
And the false negative rate had better be small, too.
Something 99% accurate is far from good enough; if only 0.01% of possible individuals are actual targets, you'll be getting 100 times as many false positives as correct positives.
Will I use my alias name which is Alain Williams, or will I use my real name which is Osama Bin Laden the next time that I book a flight to the USA ?
The trouble with this sort of thing is that it inconveniences Joe Public while doing little to deter a real terrorist.
Your point is very valid if there is a reasonable and rational discussion of the tradeoff's - You know kind of Type I and Type II errors. But the Bushies don't believe in that. Goebellian Ashcroft said that they are willing to use every legal tool available to them to achieve their goals - even if it means ignoring the spirit of the law, and reinterpreting the letters of the law to do whatever they want.
The willingness, in fact eagerness, to overlook collatoral damage is the Hallmark of the Bush Administration. They have rammed policies that wouldn't pass muster support anywhere. It is almost as if they are willing to kill 9 innocent people to prevent the 10th guilty one from escaping.
This mentality shows up in the No Fly list. It shows up in how the Arab immigrants were rounded up, and are now being deported by the thousands. It shows up in how to get to the Saddam "WMD's" they were willing to slaughter Iraqi's. Two or 3 Sept 11 bombers entered with Student visa's so everyone on that visa now gets grandly screwed.
So, logic applies only when the hysteria subsides. If you want you can never let the hysteria subside. And Donald Rumsfeld is a genius - almost lunatic - in that. Like he said in almost poetic form, on Feb. 12, 2002, Department of Defense news briefing, (which means that he could use the concept described in his "poem" below prove anything that he wants - it is almost like dividing by Zero.)
To see a world in a grain of sand, and then to step back and see the beach where the sand lies
One of the major clinical automation systems used in American hospitals uses soundex as a primary matching algorithm for patient lookups in the admitting department. Everyone is smart enough not to use it for names like "Juan Garza," but for names like "Steve Franklin" the chance of getting false-positives on your search algorithm is REALLY high. This is largely because of how the system itself implements things.
Two notable occasions have occured where patients were admitted as the incorrect "Steve Franklin" (name make up for use here, of course). Needless to say, this might be a bit of a problem when the medical and nursing staff then takes that admission record and looks back at labs, radiographs, and such ON THE WRONG PATIENT.
Of course, this same "highly advanced" system is really just a set of SQL tables that don't even use variable lengths for fields like comments (instead restricting the user to something obscene like 38 characters). The user interface is really just a Curses program that reads the columns on the table and displays them, allowing the user to edit them. Nearest I can tell, SQL functions handle all the data verification and such, and don't even do a good job at it.
I've worked with this computer system for four years, suffering through it's stupidity.
The point is that one should never assume that sucky, disgusting software is written by first year comp sci majors. There are enough professional programmers out there to cause a far bigger disaster.
Never underestimate the power of stupid people in large groups, or in corporate culture.
Who cares what algorithm they use? Why someone would support a 'No Fly' database is beyond me.
I think people are either criminal (means they should be kept in prison) or not.
Guys like you make me really afraid. For you it's only a technical problem, is it?
You US folks could really do with a constitution to stop this sort of crap happening. Oh wait, you do have one. Oh well, back to the drawing board. Land of the free indeed.
...as long as they're barred from entering the cockpit. The success of the 9/11 attacks can mainly be credited to 1970s-era hijacking guidelines directing pilots to comply with the terrorists' demands, on the assumption that they were going to fly the plane to Cuba or something similar, rather than use it as a weapon. Those guidelines made sense in their time, but clearly, they're no longer applicable.
Here's an idea -- instead of inconveniencing millions of innocent passengers, how about securing the cockpits instead? So long as the pilots remain in control of the plane, it's a flying prison for anyone who commits any criminal act back in the passenger compartment. Let the cockpit crew notify the ground of a failed terrorist attack and land the plane at the nearest airport, with the police and FBI waiting. End of story.
Perhaps if airlines weren't so elusive about their pricing, potential passengers would be able to easily compare various flight options without having to do this. But obviously it's in the interests of the airlines to keep passengers in the dark.
I had to change a flight that I was booked for a couple of months back, and I couldn't even get them to give me a firm figure on how much it would cost to alter it until I'd committed myself to doing that. Now that is ridiculous.
-- Even if a god did exist, why the fsck should I worship it?
Interestingly enough, the original Soundex was based on English language only. So when feeding it foreign names, it will obviously match names from different languages that in reality are far from sounding alike. Admittedly, their algorithms are merely based on Soundex and maybe a bit better.
But to me, finding terrorists by checking their names against no-fly lists sounds just about as useful as checking IP packets for an Evil bit, doesn't it?
In the US, more people are killed in car accidents _every month_ than were killed in the attacks on the WTC. Even a tiny 2% decrease in the number of car-accident deaths would save more lives every decade than were lost in all terrorist attacks the US has ever suffered.
Over the last 10 years, an American's odds of dying in a terrorist attack are about 1 in 100,000. That's less than your odds of drowning in your own bathtub, less than your odds of drinking yourself to death, and less than your odds of accidentally suffocating in your own bed! (http://www.nsc.org/lrs/statinfo/odds.htm)
Frankly, the current atmosphere of fear of terrorism is little more than hysteria. Why on earth aren't we showing the world we have some balls and are strong enough to not let a few terrorists make us live in fear? If you live in fear or give up freedoms, you've let the terrorists win!
X-raying shoes doesn't make for effective security, but it's intrusive enough to give the impression that at least something is being done.
Articles and editorials that call attention to the violations that come with the bogus no-fly list are essential components of the system -- they make everybody else experience it, vicariously. Everybody who is a little bit stupid (i.e. most people) feels a little safer for it. Sure it inconveniences some people, but not enough to make much political difference.
Even better than the impression of intrusive security, it leads to demands for what amounts to a system of internal passports, where you can't travel by air without registering, and getting -- and maintaining --- official permission. "What, no internal passport? Sorry, sir, I can't let you board." At first felons will have their passports pulled, then "suspected terrorists", then political undesirables of all sorts.