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False Positives, Few Matches Plague 'No-Fly' List
Posted by
timothy
on Sun Jun 08, 2003 03:47 PM
from the measure-twice-cut-once dept.
from the measure-twice-cut-once dept.
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."
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Politics: Congress Debating "No-Work" Database 438 comments
grag writes "Cnet is reporting that the US Congress, in their quest for immigration reform, seeks to force employers to utilize a database to determine a person's eligibility for employment. The Department of Homeland Security would operate the database and would be given access to IRS records for this purpose. The article mentions similarities between this proposal and the no-fly list — and the expectation of similar difficulties the proposed database could pose to valid people seeking employment."
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Soundex??? (Score:5, Interesting)
Re:Soundex??? (Score:5, Informative)
Hey, wanna make a good living in these uncertain economic times? Come up with a better alternative and propose it to DARPA [darpa.mil]. There is actually some very cool research going on that is funded by DARPA in terms of biometrics and database centric comp sci.
Parent
Re:Soundex??? (Score:5, Insightful)
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.
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Re:Soundex??? (Score:5, Insightful)
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?
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Re:Soundex??? (Score:5, Funny)
On my course, in the section on name recognition, we first learned Soundex, and then learned Obershelp, along with the fact that the latter is far more accurate, and Soundex is pretty crap.
Perhaps it was written by people with no education..
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Re:Soundex??? (Score:4, Informative)
Obershelp/Ratcliffe works well for finding the best match in small sets, but on a large DB, it breaks down completely unless you are willing to dedicate significant time to the search. While better alternatives to Soundex definetely exist, Obershelp/Radcliffe is not one that should be used in large databases.
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Re:Soundex??? (Score:5, Insightful)
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?
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Re:Soundex??? (Score:5, Funny)
Are you trying to tell me that the RFC 3514 patch I wrote for the Linux kernel back in April is useless?!
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Heard about this (Score:5, Funny)
Deal-Hunting is illegal? (Score:5, Insightful)
I understand that the airline industry is a little tight right now, but that's just insane.
Re:Deal-Hunting is illegal? (Score:4, Funny)
I understand that the airline industry is a little tight right now, but that's just insane.
Yeah, the current administration wants everyone to be paying full fare here. We gotta start getting this economy back on track, so those that refuse to participate will be identified as terrorists and placed into the TIA archive.
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Re:Deal-Hunting is illegal? (Score:5, Informative)
Even though you bought two complete return fares, it's still cheaper most of the time that buying one return ticket during a business week. They are trying to fleese the business traveller to subsidize the vacation traveller. I think you probably get both sets of airmiles from buying 2 sets as well
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Re:Deal-Hunting is illegal? (Score:4, Informative)
The two tricks are "hidden cities" and "double-booking." For a hidden city, you book a flight through where you really want to go, get off the plane, but have a remaining segment. Since you had to make a stop, that ticket is cheaper.
The airlines really have a flawed pricing scheme. Maybe it made sense 15 years ago, but they really need to re-consider based on
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The problem... (Score:5, Insightful)
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.
Re:The problem... (Score:5, Insightful)
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Re:The problem... (Score:4, Funny)
So you just have to replace the current population?
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Or safer cars. And bathtubs. (Score:5, Insightful)
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!
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Re:The problem... (Score:5, Interesting)
Heck, there's a guy on death row with the exact same name as me out there somewhere...I'd hate for this great idea of the government to lead to my law abiding ass getting thrown in jail even "just in case"
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Re:The problem... (Score:5, Funny)
I've been hollering that rednecks shouldn't be allowed to drive trucks (or anything else) since I moved to Texas in '96.
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Re:The problem... (Score:5, Insightful)
This is a system designed to give you a false sense of security. It bothers and harasses people so much that they feel safe when they get on the plane (if the plane doesn't leave before they get through the bullshit). It will not stop the next hijacking at all- although it strongly discourages discretionary air travel, and is rapidly destroying the airline industry.
We should go back to the system we had before 9/11, that served us well for many years. Terrorists may still be able to crash airplanes, but they will no longer succeed in crashing airplanes into buildings. Now that everyone knows how that type of attack works, it is unlikely to succeed again. Note how it didn't even succeed once they got wind of it via cellphone during that flight over Pennsylvania.
But since the public has it in their head that terrorism can be magically prevented at the airport somehow, we should put up some sort of pretense for them at the security checkpoint and the gate. I'm thinking about some sort of prop that you would see Scotty using on Star Trek- a sort of stick with colored lights inside that you wave over a person. If they're a terrorist, the lights turn red and the stick makes a funny sort of buzzing noise. That way we could wave people through, and have them convinced that they've been inconvenienced enough to be safe.
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Re:The problem... (Score:4, Insightful)
Terrorists don't have "careers" anymore.
Particularly suicide terrorists.
We should go back to the system we had before 9/11, that served us well for many years.
We should go back to the system we had in 1965. You want to fly somewhere, you buy a ticket.
Occasionally someone tries to steal/crash the plane. Occasionally that works, occasionally the pilot or the police or someone makes a few holes in the would-be bad guy. Nobody suggests a need to violate everyone's rights to try to stop the rare crazy person.
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Re:The problem... (Score:4, Interesting)
>Particularly suicide terrorists.
That was my point. It used to be that these people would take over a plane, force the pilot to land somewhere, maybe off a passenger or two, demand transportation for their escape, and maybe even put hoods over their heads and give a little press conference before leaving- presumably to hijack again some day. Afterwards we would figure out who they were, put their names on lists, and maybe even look out for them.
Now we have rookie terrorists committing suicide and mass murder with no explanation, and everyone is simply left to assume that it has something to do with Israel and Palestine. Our lists are useless. We seem to be looking for retired terrorists and punk rockers from the seventies, and if your name sounds like a name on the list you can't fly. The terrorists won!
We should go back to the system we had in 1965. You want to fly somewhere, you buy a ticket.
Personally I would prefer that this bizarre security not be applied to all air travelers- it should be considered an amenity. If you want to ride on a "terror-free flight" (and you're innumerate and stupid), you pay an extra $50-100, get there a few hours earlier, eat your in-flight meal with those plastic butter knives, and rest comfortably with the knowledge that punk rocker Johnny Rotten Lydon (rhymes with "Laden"?) is not on the plane with you. Also nobody from Priceline.
Parent
Re:The problem... (Score:4, Insightful)
from the Jargon file:
wave a dead chicken: v. To perform a ritual in the direction of crashed software or hardware that one believes to be futile but is nevertheless necessary so that others are satisfied that an appropriate degree of effort has been expended. "I'll wave a dead chicken over the source code, but I really think we've run into an OS bug."
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Re:The problem... (Score:4, Insightful)
It's a lot like the AIDS/HIV test. You want every potential positive test to show up so you can follow it up but you do not want to miss a potentially infected person.
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Re:The problem... (Score:4, Interesting)
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Re:The problem... (Score:5, Insightful)
Normally every medical test in fact consists of two tests. The first one is called the efficient test, the second one the effective test.
The first one is to throw out as much uninteresting people (the ones without any sign of sickness) as possible without missing any of the interesting people (the ones that are sick). In Computer Science you call a test like this "Trivial Reject". It should be fast and cheap to save on costs (of every type, like monetary, computational time...).
The second test is supposed to catch as much of the interesting people (sick ones) as possible while throwing out pretty surely all of those who are in fact healthy and thus uninteresting for the matters of the test. This leaves you with a test population which consists of almost all sick people and some very few false positives. Because of the shrunken number of persons this test can be more elaborate and expensive.
The problem with all those tests is, that with the low frequency of the usual dangerous plague you are testing for, the false positives (even though they may be very small compared to the whole of the population) still contains more people than the actual sick ones. I remember some exercises where we had to calculate the risk of actual being sick after a positive test for given frequencies of occurance of the plague in the population and the characteristics of the test. Often the result was that you have a 99% chance of being a false positive even though the test itself was pretty good.
Same is valid for the frequency of the actual terrorists in the population of all U.S. domestic flyers. While there were 19 terrorists in the 9/11 attack, there have been billions of individual flights in the recent years. If your tests are being 99.999% sure in clearing a innocent flyer, it would still mean that this test applied to one billion flight passengers gives you 10 000 false positives.
(This number is one of the reasons why the Romans once decided for "in dubio pro reo". Because the number of lawful citizens is quite high compared to the number of criminals, the average screening of larger populations results in more false positives than actually caught thieves. So you have always to prove individually that someone is guilty beyond any doubt before you can actually call them guilty.)
In this special case the screening for names itself is a very inaccurate test. There are names in some countries being too prevalent to distinguish between people. For Corea it may be the name 'Kim', for India 'Singh', for Russia 'Gorbachev', for the U.S. 'Smith' or 'Adams'.
The inapprobriate way to match spelling and pronouncing with the Soundex system (which only works with english names) just adds to the problem. In french names you often can't make a difference between 'en', 'an', 'on', 'ent', 'ant', and 'ont'. Famous are the words 'son' (his/her, but also tone), 'sont' ([they] are), 'sans' (without), 'sang' (blood), which are all pronounced the same.
In german names there is no difference between 'tz' and 'z' or between 't', 'tt' and 'dt'. For my family name I know of the spellings 'Sigmund', 'Siegmund', 'Siegmundt', 'Sigemund', 'Siegemund', 'Siegemundt', 'Sigesmund', 'Siegesmund', 'Siegesmundt', 'Zygmunt', and 'Zygmont' (it appears that no one I ever met was able to spell my name right without me helping him, I have several documents with a falsely spelled name...).
Add to this list the number of falsely entered records (people accused of things, later cleared, but not erased from lists compiled while they were under suspicion, typing errors, missunderstandings...). So I am quite amazed that the SFO airport had only about three hundred false positives. On the other hand there were no rightful positives (no one got convicted of terrorism yet who was caught with the CAPPS system), and we don't know about the false negatives (actual terrorists flying without being caught) because they slipped through the controls.
Parent
It doesn't matter who gets on... (Score:4, Insightful)
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.
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Re:The problem... (Score:4, Insightful)
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Obviously this would happen (Score:5, Insightful)
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.
But Bushies don't care Re:Obviously this would (Score:4, Insightful)
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.)
Parent
Will I use my alias name ? (Score:5, Insightful)
The trouble with this sort of thing is that it inconveniences Joe Public while doing little to deter a real terrorist.
Re:Will I use my alias name ? (Score:4, Insightful)
I see you have an extranous "practically" in your response.
Seriously, a friend of mine was driving from Denver to Kansas City at the start of the year, and a cop pulled him over for "crowding the center line". Now, I realize that some Kansas cops are just incredibly bored, but get real.
Oh, and of course the cop asked if he could look in the trunk. If Keviee had said "not without a warrent", I'm sure he would have been taken in for acting "like he was hiding something".
Face it, everything that has been done in the name of "the war on terror" has been nothing but a power grab to remove the rights of US citizens.
Parent
Man... (Score:5, Funny)
Ten Problems with Soundex (Score:5, Informative)
Uhh... metaphone? (Score:4, Informative)
Pity the unfortunately named (Score:5, Funny)
Soundex gives each name a key using its first letter and dropping the vowels and giving number codes to similar-sounding vowels (like "S" and "C"). The system gives the same code, L350, for "Laden" and all similar-sounding names: Lydon, Lawton, and Leedham.
Boy, I'd hate to be a guy with a name like "Sam Lawton" or something. I wonder how many similarly-named middle-aged salesmen are getting red-flagged on flights... because you just never know, what if Osama Bin Laden disguised as a portly white guy from Milwaukee, and he never bothered to pick a false name that sounded sufficiently different from the original.
Reinventing the wheel (Score:5, Informative)
This sounds like the work of some consultants with no idea of what they are faced with and fresh out of collage where they have analyzed a couple of algorithms... sorry - I have had way too much of these running around the office lately
If for once someone would just poke his head out and instead of trying to find a solution to an age old problem, look and see how others are handling it, we (taxpayers) would all be much more content (and safe...).
Just my 2c.
David Nelson [TSA most wanetd??] (Score:5, Interesting)
But, you feel safe. Don't you?
OLD SOFTWARE!! (Score:4, Funny)
When they said the software was old, boy did they mean it!!
Why not use ID#? (Score:5, Informative)
But at least in here in sweden basically anytime you book a flight you give your ID number (similar to a social security #)
Two benefits:
1. Name is just a courtesy, so doesnt really matter for security if somebody get my name wrong.
2. On checkin, it must be _you_ not somebody with a similar name
Of course IDs can be stolen or forged, but that is a problem regardles of how you ID your self.
credit checks - wtf? (Score:4, Informative)
What in the hell? I was under the impression that having a credit check actually hurts your credit history [as in, you shouldn't have too many credit checks in
I always hated flying, now I'm starting to hate air lines...
Re:credit checks - wtf? (Score:5, Informative)
Parent
You need a constitution (Score:5, Insightful)
false sense of security (Score:5, Interesting)
I think I will be flying private planes if they start looking into your credit. A credit check could be like "Well, you evaded child support and paying the bank $5,000, we can't let you board, if you have the money for a flight, you can pay them!"
They know they they won't be able to get this to work right, they are just pocketing money and putting out a crap system, but I think that it may have better use for private organizations, such as "Well, he evaded taxes and bills, but we see him having a one way ticket to (place), search for him there."
Good news for potential terrorists, then ... (Score:5, Interesting)
This had me laughing so hard... (Score:5, Funny)
From the article:
Hate to break it to these guys but neither "S" nor "C" are vowels. Heck, they don't even make vowel sounds.Geeze, no wonder the system is broken.
John Gilmore is suing for freedom of travel (Score:5, Informative)
From the website:
He does so "because he believes persons have a right to travel by air without the government requiring that they relinquish their anonymity. No security threat is as important as the threat to American society caused by erosion of the right to travel, the right to be free from unreasonable searches, and the right to exercise First Amendment rights anonymously."
Check out the FAQ's [freetotravel.org], which are well written and explain the other reasons - including being subject to secret laws - he is opposing this.
Working Just Fine (Score:5, Insightful)
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.
Re:Deal hunting? (Score:5, Informative)
Story: to catch deal-hunting passengers making duplicate bookings.
This means that people were using different travel agencies to reserve lots of seats on the same flight, and then simply going with the agency who quoted the lowest price. This means that the seats end up being empty, and the rest of us end up paying for them. Sorry, but even the "rich elite" can no longer make duplicate reservations. Almost all airlines now use software to automatically cancel duplicate bookings.
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Re:Deal hunting? (Score:5, Insightful)
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.
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