I understand your point completely. You dont subscribe to 100% accuracy. My question was, what evidence supports your conclusion of a nebulous but fabulously high success rate of the polygraph?

What part of "almost always" do you not understand, Bill?

on what basis do you maintain that? What sort of polygraphs do you typically do? what empricial evidence leads you to that conclusion?

some background--I spent 14 years trying to get into the FBI, made it to the very end, got accused by a polygrapher of being a drug dealer and booted. I have never touched a drug much less sold it.

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That's right, Bill. I believe it is possible, with very much practice and feedback, to produce polygraph charts that appear legitimate while using countermeasures. I can't even do it myself in lab conditions with another polygrapher trained in counter-countermeasures, though. If I can't do it, I believe the average reader on this website can't do it, either, and I've caught some of them trying. When that happens, their job opportunity ends right there.

The truth is all that polygraph examiners and the agencies or organizations that employ them desire. Polygraph examiners aren't like Saruman, the evil wizard in Lord of the Rings, looking in their crystal ball and trying to work the arts of black magic. When examinees pass the exam, it's nice for everyone involved. When they fail, I maintain that it is almost always because they deserve to fail.

LBCB,

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My point is that it is quite possible I am sure to produce CMs that are absolutely undetectable, but that it requires a bit of knowledge and experience about what a "winning" chart looks like and how the scoring works. Going in without that knowledge leaves a lot to chance. 

Besides to my point of view, the whole CM argument is spurious. What really matters is the truth and a correct result, whether that happens by chance or by design. An innocent person using CMs and passing is a better result than a False positive, wouldnt you agree? Or are you going to argue that the process is more important than the truth? At the end of the day, that's whats this site is about--arriving at the truth. 

Apparently I hit the million-to-one lottery three times in a row on three different polygraph exams.  All of them for different issues.

It would seem logical that if I showed deception in my answers about selling cocaine on my first polygraph exam that I would show some reaction to the same question on subsequent exams, but that never happened.

I wonder what the odds are of hitting a one-in-a-million shot three times in a row?  I believe the odds of that happening are one time in ten to the eighteenth power.  I think that's approaching what even statisticians call "impossible."

LieBabyCry Wrote
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Do polygraphers (and Dr. Phil  ) not have an agenda in trumpeting a polygraph's alleged accuracy as 999,999 in a million (in your case) or 92% (in Dr. Phil's case)?

Who should an uninterested party believe, you or Dr. Phil?

Ok, perhaps one in a million is a slight exaggeration. Let's look at in another way, though.  How many people who have posted on this website are false positives? In this age of the internet, I think that there are a lot of people out there taking polygraphs who come to this site out of curiosity, and I'm sure you would like to think you have that kind of audience.  Well, since you began keeping count, there have been just over 20,000 posts on this website.  Over 3,500 of those have been yours, George.  That leaves less than 17,000 posts.  How many total posters wrote those 17,000 posts? Surely less than 10,000 posters, judging by the enormous number of posts by many of the Especially Senior Users and Senior Users.  But let's say that every single one of those posters has been a false positive failure in a polygraph exam. I'm sure that would be a ridiculous exaggeration, but let's give it a ridiculous benefit of the doubt. How many polygraphs have been conducted in the U.S. alone since you began this anti-polygraph crusade?  Any idea?  No?  Me neither.  But if you took all of those posters we're pretending are false positive failures, I think it would still be a tiny minority compared with those who passed the polygraph or simply came up inconclusive.

I had fun with this post, as I'm sure you can tell. But it is fun food for thought.   

LieBabyCryBaby wrote on Nov 21^st, 2006 at 11:32pm:


The NAS's above-cited finding necessarily entails that false positives are not unlikely.

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What documentation supports this assertion?

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Why would they?

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That's a conclusory argument. On the basis of what evidence do you conclude that false positives are a "tiny minority?" Consider that pre-9/11, the FBI's pre-employment polygraph failure rate was about 20%. Post-9/11 it suddenly rose to about 50%. How can such a sudden departure be consistent with false positives being a "tiny minority?"

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I don't pretend to know. But considering that the FBI has administered fewer than 1,000,000 pre-employment polygraph examinations since it began pre-employment polygraph screening in 1994, those who have wrongly failed the FBI polygraph know from personal experience that your suggestion of a one-in-a-million false positive rate is overly optimistic.

George, even if you insist on discounting my experience (and, sadly, I must remain anonymous for legitimate reasons I'm sure you would appreciate), the NAS never said that the false positive was even a likely result. If you take all of the correct decisions made in correctly administered polygraph exams, and then throw in the inconclusives, the false positives and false negatives would indeed be a tiny minority. And you don't see the false negatives on this forum complaining do you?  

So that leaves us with a tiny minority of claimed false positives, of which you are one. And how many of those false positives know anything about the polygraph except what they read and choose to credit or discredit? And how many of them have any experience in the real world as polygraph examiners?

LieBabyCryBaby wrote on Nov 21^st, 2006 at 11:07pm:


I see. So a neutral observer without my "baggage" should accept your word for it, based on your (anonymously and unverifiably) professed experience, that the risk of a false positive outcome in a polygraph examination is 1:10^6. Yet somehow, the National Academy of Sciences did not accept such a notion, finding instead (at p. 202 of The Polygraph and Lie Detection) that "almost a century of research in scientific psychology and physiology provides little basis for the expectation that a polygraph test could have extremely high accuracy" (original emphasis). How do you explain this? None of the authors of this report were saddled with my alleged "baggage."

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Because a neutral observer doesn't carry the baggage of your personal agenda, George. Without that baggage, it's easier to trust experience over lack thereof.

LieBabyCryBaby wrote on Nov 21^st, 2006 at 10:51pm:


An estimate based on what? Why should a neutral observer accept your estimate?

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It's an estimate, George, ok?  No, I haven't conducted one million polygraph exams yet.  But from personal experience I can tell you that my estimate is more likely than the sky-is-falling dramatic exaggeration of "false positives" claimed by this website.

And Brandon, although there is bitterness in your humor, I do appreciate your humor.   

LieBabyCryBaby wrote on Nov 21^st, 2006 at 10:37pm:


Great.  My chance to win the lottery was wasted on a simpleton with a physio-gadget accusing me of lying.  Yeah, now I feel better.

Had the wonderful false positive polygraph opinion not cost me the chance to complete further hiring phases with the agency which conducted the "test" and another agency that immediately tossed my application due to the same test I may very well have gone on my merry way.  But unfortunately that did not happen.

No matter what anyone says, I am aware that false positives do occur much, much more frequently than 1/1,000,000.  That's just bad math.

LieBabyCryBaby wrote on Nov 21^st, 2006 at 9:11pm:


On what basis do you maintain that the risk of a false-positive result is 1:10^6? Please be specific.

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Well, I guess you win the lottery.  The other 999,999 people go on with their lives and don't frequent this website. 

LieBabyCryBaby wrote on Nov 21^st, 2006 at 9:11pm:



a 0.0000001% chance of being a false positive?

Respectfully, I call bullshit.


But now I feel very special knowing that I was 1 in a million.  1st test accused of drug activity (false-positive); 2nd test cleared of drug activity, and 3rd test cleared of drug activity.

Yes, bullshit I say.

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True, you may end up inconclusive.  Or you may get caught using countermeasures when the truth without countermeasures would have landed you the job.  Or, to give people like George the benefit of much doubt, you might be that one in a million who "undeservedly" fall way down into negative numbers and fail the exam.  Yes, a real crap-shoot.

LieBabyCryBaby wrote on Nov 21^st, 2006 at 8:38pm:


The underlying procedure (CQT polygraphy) is a crapshoot: telling the truth is no guarantee of passing. Given the availability of simple, effective countermeasures that polygraphers have no demonstrated ability to detect, those whose futures rest on the outcome of a polygraph crapshoot have little to lose, and potentially much to gain, by employing countermeasures.

My point exactly, Bill.  Countermeasures are a real crap-shoot, and becoming more so as time goes by and more examiners receive additional training.

its not that simple. you have to have an understanding of what the appropriate level of effort is required to produce an adequate and not overly large physioloical change. Also, you have to have the correct timing because only a short portion of the time between questions is the scoreable range. On my tests the scorable rnage was right after the question was asked and maybe 1 or 2 seconds after the answer, not right after the answer as you might expect.

bottom line-CMs take practice and knowledge or its a real crap shoot.

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This is quite an admission by you, George.  Yes, this is true.  While an examinee can try to do many things to influence the pneumograph channels, the cardio and electrodermal channels will usually betray him/her.  It is when these betrayals are consistent on the relevant questions despite the countermeasure attempts on the "control" questions that the examinee will be caught in the act.

While countermeasures may mitigate the risk of a false positive outcome, they do not offer certainty that one will pass. That said, it appears that you have understood the essential elements of polygraph procedure and countermeasures. Keep in mind, however, that there is little one can do to prevent cardio reactions to relevant questions, and I think it is pointless to try. You might also bear in mind the behavioral countermeasures outlined in Chapter 4.

I will be going in for a polygraph for a job with the Canadian Government in the next couple days... now I have nothing to hide but know that shit happens regarding polygraphs... I have read "The Lie Behind the Lie Detector" a few times through... and am confident I can pass it... so this is basically what I have in mind...

I have naturally sweaty hands so theylll sweat through the whole thing.. shouldnt be a problem

Go into the polygraph, act like a dummy like I know nothing about polygraphy... act like I think the polygrapher is on my side

Maintain a steady breathing pattern the whole time through until the sensors are unhooked from my body

Raise my cardio activity (through method of doing math in my head) when I get a control question... and block my breathing activity for 4-5 seconds AFTER I answer the question

Keeping up the steady breathing pattern and with a lower heartbeat (cardio activity) than the control question, answer the relevant questions...

maintain the steady breath/cardio during the irrevlant questions (although they dont matter)

ADMIT NOTHING, tell as little as possible...


should I be OK?