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Replacing Metal Detectors With Brain Scans
Zordak writes "CNN has up a story about several Israeli firms that want to replace metal detectors at airports with biometric readings. For example, with funding from TSA and DHS, 'WeCU ([creepily] pronounced "We See You") Technologies, employs a combination of infra-red technology, remote sensors and imagers, and flashing of subliminal images, such as a photo of Osama bin Laden. Developers say the combination of these technologies can detect a person's reaction to certain stimuli by reading body temperature, heart rate and respiration — signals a terrorist unwittingly emits before he plans to commit an attack.' Sensors may be embedded in the carpet, seats, and check-in screens. The stated goal is to read a passenger's 'intention' in a manner that is 'more fair, more effective and less expensive' than traditional profiling. But not to worry! WeCU's CEO says, 'We don't want you to feel that you are being interrogated.' And you may get through security in 20 to 30 seconds."
Right now it is used to find terrorists, but this technology can be used in reverse. Flashing images of the president and the national flag, anyone don't respond positively get singled out... Such uses are very disturbing.
Where is the "Ignorant" mod tag?
Frankly, about the only sinister thing about this is that there are people in officialdom who are so fundamentally brain-dead they actually believe the claims of whatever idiot is trying to sell this.
Even when interrogators have the time and money to hook people up to the most sensitive equipment available there is no technology that can determine to reasonable accuracy whether a person is lying in answer to a given question, nevermind their exact mindset or intentions in the next few hours.
Now we are supposed to believe that some gadget can automagically determine whether or not somebody wants to blow up a plane when they walk past it and are flashed a "subliminal image" of osama bin-laden?
I could go on about the sheer idiocy of assuming that somebody's reaction to a popular hate figure defines their politics or intentions. I could start about how peoples wildly varying mental states and physiologies make such simplistic measurements useless. But frankly it's not even worth deconstructing an idea this stupid in detail. Anybody dumb enough to believe in this fairy story clearly either suffers from paranoid psychosis or is so mentally deficient as to be beyond any form of rational argument.
They say its only 20-30 seconds in security, until you realize that Bin Laden reminds you of you buddy's Moses costume last from Halloween when he kept drunkenly telling all the women to "part their legs like the Red Sea". Suddenly your subliminal responses swing the wrong direction and you end up being held in more traditional interrogation for hours to months in some dark hole halfway to Hell.
Common Sense isn't as Common as people think...
Actually, let's do...
What many people don't realize is that detection procedures with very impressive-sounding statistical properties generally do horribly at catching rare events.
Imagine some very impressive numbers. Suppose that this procedure has 99.999% sensitivity -- it catches nearly every wannabe terrorist who tries to board a plane intending to do harm. And suppose it also has 99.999% specificity -- out of 100,000 innocent passengers, 99,999 will be correctly identified as innocent, and only 1 will be a false alarm. Sounds good, right?
Not really. In a given year, only a very small number of passengers are wannabe terrorists -- say, 10 per year. (That's probably high.) On the other hand, there are 1.6 billion air passengers per year (that may be a low estimate, since it's a 2000 number). So if this were implemented worldwide, then in a given year, we can assume that this profiling procedure will flag 160,010 people as terrorists. Only 6 x 10^-5 of those will be actual terrorists.
Of course, those hypothetical sensitivity and specificity numbers are unrealistically, ridiculously good. With more realistic numbers, the problem gets much worse. Even if the detection procedure is very sensitive and very specific -- and I doubt that it is -- the low base-rate of terrorism means that an enormous number of people will be falsely accused of being terrorists.