And it’s not cancelled. It’s got a new season. 5 people now instead of 3. A week in the parent’s home instead of a weekend.
To my knowledge, polygraphs have NEVER passed a controlled test of their accuracy. I took one and I am sure the teck was gessing about the answers.
Utter rot.
It is nothing but a stress or reaction detector and no peer reviewed research supports the suppositions – they are just that suppositions – regarding the biometric responses.
An unsupported assertion. When you are giving a response in which little thought is involved, there is little response perhaps. Other than that, any number of things might provoke a response. And insofar as there is no research, peer reviewed properly scientific controlled research, supporting anything further, the polygraphy is nothing but an interregator’s tool of no more validity than simply playing other mind games with suspects.
By the way, you may look to the Federation of American Scientists for a handy compilation of links, including several actual scientific studies, on the polygraph.
http://www.fas.org/sgp/othergov/polygraph/index.html
Unsurprisingly, the scientific community takes an extremely dim view indeed of the polygraph, the claims for which have yet to be verified by proper investigation and research. Faith based “science” and mere assertion are what are behind this little bit of modern voodoo.
The whole original question about reformulating the question in your head and answering that question reminds me of a scene on a show I saw recently (I think it was one of the Law and Order shows, or maybe CSI) where the person administering the test was using one of the officers to calibrate the machine. During the calibration, one of the questions she asked him was, “What is three times five?” or something like that, and everybody looked at her like she was nuts, and she said “Mental calculations read as lies.”
So, assuming that’s correct (and it sure seems like it should be, from the nature of a polygraph machine), I’d imagine that the mental activity of reformulating the question would do the same thing, and read as a lie anyway.
Also, on the topic of Phnord Prephect’s “BLIP detector” theory, that sounds like exactly what the relatively new “mental lie detector” that I read about a while back does – the one that measures your brainwaves while showing you a series of images (I don’t know if it only works with images, or if it could work with questions being asked as well) associated with the crime, and seeing if you recognize things that only the criminal would recognize. Although it seems to me that it would be pretty tricky to come up with images that would be recognized only by the criminal, and not by witnesses or victims or whoever else might have been there when the crime occurred. In any case, does anybody have any more recent information on these “lie detectors”? Have they actually proven useful yet?
My uncle was a cop, and he said that he liked the lie detector to see the reaction of the person - not to the test, but just the idea of a lie detector test. When I worked for a supermarket, they came in one day and gave us all lie detectors tests. Three guys (out of eight) quit on the spot rather than take the test. The big question was if any of us ever stole anything - we all took things like sodas or candy bars - so the only honest answer was yes. they asked if we stole, then what we stole - and they never gave us any grief about it later.
Since its my OP I’ll take this off into a new direction. Mods if it is still unsuitable for GQ, please feel free to move it.
Lets say you’re being questioned about something - a theft for example. You’re asked if you stole the item in question. You re-formulate the question mentally to make it look like you are lying, and then answer ‘Yes’.
What carries more weight in the interrogation? Your admission or the fact that the polygraph indicates this admission to be false?
Collounsbury is indeed correct. The noted magician and paranormal debunker James Randi has a blurb in his weekly column on this very subject here.
While answering in the affirmative to a question asking if you had stolen while trying to generate a “lying” polygraph result would be risky at best, since there are no standards, the conclusion would be at the whim of the individual examiner.
I’d bet most would not interpret that result as a lie.
Sorry dopers - I should have made it clearer that is this instance, you are guilty :smack:
Seems as if the best way to fool a lie detector would be to get hold of one and practice.
It also sounds as if the operator is in the position to personally decide what the results show. He could decide who’s found guilty, who doesn’t get hired, etc. Being human, he could do this either deliberately or unconsciously.
So your best bet is to be tested by someone who is like you, and/or to try not to rub the operator the wrong way.
Whether the operator likes you isn’t a big factor. Not showing the operator any behaviors associated with lying (avoiding eye contact, excessive fidgetting etc) or giving the impression of actively concealing those behaviors is important. If your body language etc give the operator the impression that you’re lying, he’s more likely to interpret the readings that way.
What The Machine Actually Detects
A few of the posters don’t seem to have a clear idea of what the machine actually consists of and what it does.
photoplathysmograph-this fits on a fingertip. A red led flashes and a sensor reads how much of the light is reflected back from the skin. The more blood there is in the skin, the less light is reflected. The ppg also doubles as a heart rate monitor.
galvanic skin response-just two of the right kind of electrodes stuck in a spot where muscle activity won’t interfere with the readings.
pneumatrodes-sealed tubing that is stretched across the chest. Breathing cause the tubes to expand and contract. These are used to record how deeply you breathe and how often.
If you feel you must, you can add a blood pressure cuff and EKG.
I know of no lie detector that incorporates EEG. Its expensive. You need a lot of electrodes(OTTOMOH-3 for each channel you want to monitor. One on the site you want readings from, one nearby, and one ground. The software filters out any shared readings, gsr, muscular activity, static, etc, and gives only information from the one electrode.). Most importantly, it’s impossible to get decent EEG readings from a talking subject. The noise from the jaw, throat, and neck muscles drowns out the signal.
I have no experience with the printers you see in films. Frankly, I don’t understand why any one would continue to use them-there a specialty item and thus expensive, they can wear out, break down, etc. The stuff we sold could be easily hooked up to a pc. The sensors and the housing for their circuit boards is about the size of a toaster. All you need is a serial cable and the right software.
There is no polygraph which can function properly without a human operator. What is a baseline stress level in one person may be an anxiety attack in somebody else. Some tv shows have a buzzer and red light indicate a subject is lying. This isn’t automatic or even part of the machine. The operator decides if the subject is lying. The operator then presses the button that sets of the buzzer and light.
Bringing this thread back from the grave, prompted by a more recent polygraph question, to pose one more thought about the use of lie detectors in this sorts of reality shows… speaking of the north american version of ‘meet my folks’ specifically, I guess.
One thing that I’ve heard about polygraph lie detectors is that normally the questions are read off first before the test proper begins. The reason for this being that if the subject is surprised or shocked at hearing the question for the first time, they’ll have a heart rate reaction etcetera to the question, and thus will probably test a false negative no matter what they answer.
On “MMF”, they definitely don’t ever seem to follow the procedure of going over the questions beforehand. This automatically stacks the game in favor of the contestants flunking the worst possible questions… eg “if you go on the trip, will you sleep with my daughter” or questions trying to confirm the horrible rumor about their past that the producers keep trying to find more inventive ways of introducing.
So… to whatever extent polygraphs are more than quackery, or even if there is none, is it correct that not revealing the questions beforehand will yield false negatives… that is mistaken ‘lies’??
Or should that be false positives… being that the lie is what is supposed to be definitively identified??
This week’s episode of Joe Schmo 2 also had a polygraph. The questions weren’t read off before the test started, but all four guys were asked the same questions, so the “real” contestant was already familiar with the questions when it was his turn.