retcopper wrote on Apr 25
th, 2006 at 3:46pm:
Antrella and Mr Mystery"
What don't you get? An investigation is conducted and a polygraph exam is given. The suspect flunks and eventually confesses. What more validity do you want. I agree with you, "she is not the first to be discovered this way ". You can takse solace in the fact that as the polygrah gains more acceptance there will be many, many more "discovered this way". Especially those who use counter measures to try to hide the truth.
Retcopper,
How is this case any more valid than any other? A person was accused of something and, after “failing” a polygraph, she confessed. Or maybe she didn’t, depending on which news reports you believe.
If you are going to use this case as proof that the polygraph works then I would like to know what separates it from other cases in which people “failed” their polygraph yet continually maintained their innocence. If the anecdotal evidence in this case is sufficient to prove the polygraph’s accuracy then isn’t the anecdotal evidence in other cases also sufficient to prove the polygraph’s lack of accuracy?
I failed my first pre-employment polygraph exams before passing my fourth. Using the same methodology as you have shown in your post that means my first three were aberrations which provided no real insight into the accuracy or inaccuracy of the polygraph. But the fourth one is “proof” that the polygraph works, right?
If the polygraph actually functioned as a tool to detect deception there would be no such things as false-positives. Perhaps it still wouldn’t detect deception 100% of the time, since few tests are accurate to that degree. But if it truly had validity then you would know with 100% accuracy that if a person failed he or she must have been deceptive. As it stands now a “failure” means that the person was deceptive, or was honest and falls into the disputed percentage of false-positive, or they were honest and used CM’s improperly, or they were deceptive and used CM’s improperly.
The false-positive rate for polygraphs is disputed, of course. Supporters of the polygraph say it is very low, while people like me believe it is very high. I know of no one who asserts that it doesn’t exist. And the false-positive rate is what, in my opinion, renders the polygraph worthless as a scientific test.