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Yes, but only to to some extent.  The big problem with the PLCQT is establishing base truth. A secondary problem is the assumption that DI on controls will produce a physiological response approximately halfway between a NDI and DI on relevants AND that there will be sufficient response differential between NDI and DI.

CM's do not suffer from this, indeed they utilize scoring methodologies to produce required differentials. That said, CM's have other vulnerabilities, these being obvious ones:

1. Examinee inexperience with CM's.
2. Possible physiological signature variations specific to certain CM's (tongue biting, sphincter compression).

The first seems to be the greater one. Based on the obfuscation and fud that polygraphers publicly exhibit, it is likely the one they most rely on.

The NAS study mentioned the second as a sort of unknown, but possible, factor.

Both of these should be more amendable to study than the PLCQT as baseline truth is not at issue. Therefore it is a virtual certainty such studies have been done. Results of these, positive or negative, remain unknown.

-Marty

Marty,

My point was with regard to countermeasures to the CQT having a sound theoretical basis despite the lack of any such basis for the CQT itself. Do you agree?

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I also agree that the CQT "can" be beaten. Probably most of the polygraphers here believe the poly "can" be beaten (though few will admit to it). Asking whether something "can" be beaten as opposed to providing more specificity is am inartful survey at best. I also believe that to have a reasonable probability of beating the CQT with CM's requires one understand the polygraph quite completely. Completely enough to immunize one to the manipulations of the examiner who starts of with significant psychological advantage.

BTW, you do a very good job of that in TLBTLD, but it is still a non-trivial task.

-Marty

Marty,

Again, a key difference between the use of CQT polygraphy to detect deception and the use of countermeasures to influence the outcome of a CQT polygraph examination is that while the CQT has no sound theoretical basis, countermeasures to the CQT do have a sound theoretical basis that is consistent with known facts about CQT methodology. Which speaks to why of the 96% of Society for Psychophysiological Research members surveyed who had an opinion, 99% agreed that "the CQT can be beaten by augmenting one's responses to the control questions." (See, W.G. Iacono and D.T. Lykken, "The Validity of the lie detector: Two surveys of scientific opinion," Journal of Applied Psychology, 1997, 82, 426-433; discussed also in Chapter 12 of Lykken's A Tremor in the Blood: Uses and Abuses of the Lie Detector, 2nd ed., 1998.)

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To the extent the PL-CQT is invalid, it is hard for me to see where the use of CM's, wich depends on the theory of the CQT, is more valid. There is certainly nothing in the NAS report that suggests CM's are more "reliable" than the basic polygraph itself.

-Marty

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Marty,

Because polygraphic lie detection has no scientific basis and no diagnostic value, your foregoing argument has little relevance for the truthful applicant weighing the risks of employing countermeasures versus doing nothing and hoping that an invalid test will yield accurate results. Let's suppose that the pre-employment polygraph failure rate at a particular agency is about 50%, and that about half of those who fail are in fact deceptive. It does not follow that a truthful applicant has only about a 25% chance of failing. His chances are closer to 50%. Which was my point.

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George,

I gather most screening failures are related to drug questions. Given the endemic nature of drug usage in the US, it is highly likely many and possibly most of those 50% that failed were in fact not false positives. Still, I also suspect a large fraction of them were false positives.

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I think you are right relative to informed examinees. Understanding how the polygraph works may well make someone both less responsive to the controls and more responsive to the relevants. If that is the case, not using CM's could be a real disadvantage.

As for the case of an non-deceptive, naive examinee (who is not too honest ) vs that same person becoming informed and deciding to use CM's, I think it may be problematic unless the person seriously practices and informs themselves completely.

-Marty

Marty,

You write, among other things:

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I think you overlook a key difference: polygraphic lie detection has no sound theoretical basis, and with some agencies, the risk of failing may be 50-50 or worse.

By contrast the methodology of CQT polygraphy is well known and well documented, making the employment of countermeasures, in my estimation, a considerably safer bet than simply hoping that the polygraph will get it right.

George,

I think it is important to point out that published research into CM's is extremely limited and subject to the same uncertainties and biases of extant polygraph research. If one maintains that honestly passing a polygraph is a crapshoot it is hard to suggest that deploying CM's is otherwise.

That said, it is reasonable to infer from the blanket assertions that CM's can be detected that if in fact all stripes of CM's could be detected this information would be published in detail as a prophylactic to deter CM's. After all, the deployment of CM's by some fraction of examinees further erodes the reliability of the polygraph. Thus, the fact they are not published strongly suggests that one or more types of CM's are difficult to detect.

A concern, and one echoed in the NAS study, is that foreign entities have almost certainly conducted such research and may provide training on CM's with small distinguishing physiological signatures.

-Marty

Torpedo wrote on Dec 9^th, 2003 at 1:03am:


My consistent position has been that truthful individuals should make an informed choice regarding whether to employ polygraph countermeasures to protect against the risk of a false positive outcome.

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I'm certainly not upset with you for citing the NAS report. For the benefit of those who don't have the PDF or paper copy, here is a link to p. 139 (from which one can also navigate to p. 140):

http://books.nap.edu/books/0309084369/html/139.html

The relevant passage states (at p. 140):

"Some examinees who have not committed crimes, security breaches, or related offenses, or who have little to hide, might nevertheless engage in countermeasures with the intent to minimize their chances of false positive test results (Maschke and Scalabrini, no date). This strategy is not risk-free for innocent examinees. There is evidence that some countermeasures used by innocent examinees can in fact increase their chances of appearing deceptive (Dawson, 1980; Honts, Amato, and Gordon, 2001)." (emphasis added)

Not having read Dawson's article, I cannot comment on it. However, it should be noted that the article by Honts, Amato, and Gordon ("Effects of spontaneous countermeasures used against the comparison question test." Polygraph Vol. 30 [2001], No. 1, pp. 1-9) deals with "spontaneous" or untrained countermeasures, that is, things that people ignorant of polygraph procedure might do on their own in an attempt to improve their chances of passing.

The countermeasures described in The Lie Behind the Lie Detector are qualitatively different from the spontaneous countermeasures that are the subject of the article by Honts, Amato, and Gordon. No polygrapher has ever demonstrated any ability to reliably detect the kinds of countermeasures described in The Lie Behind the Lie Detector.

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As noted earlier, the "evidence that some countermeasures used by innocent examinees can in fact increase their chances of appearing deceptive" cited in the NAS report apparently refers to countermeasures other than those suggested by AntiPolygraph.org.

I find it ironic that you, as a practitioner of a trade that depends on lies, deceit, and public ignorance of how polygraphy "works," would characterize those who come to this site seeking to educate themselves as "faithful sheep."

I also find it ironic that you (and a number of other polygraph proponents who have posted on this message board) would liken me to some kind of cultic religious figure. As you peruse your copy of the NAS report, you may care to take a look at the section of Chapter 1 titled "The Lie Detection Mystique," in which the polygraph community is likened to a shamanistic priesthood that keeps its rites secret to protect its power.

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To paraphrase David Lykken, that which is not rocket science, and indeed, not science at all, is polygraphic lie detection.

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Many who have taken your advice and simply told the truth have been surprised to find themselves wrongly branded as liars by your voodoo science. Just food for thought.

The only thing you will hear from Torpedo is a thunderous, befuddled silence when confronted with his machine's failures (??? Gee.....they never covered that in polygraph school ???)

The truth didn't work for me, but my best friend lied on her exam and it worked for her.   Can you explain this to me?

Forgive me for being a mite slow on the uptake, but I happened to be scanning my copy of the NRC book on the National Academies of Science Report on Polygraph.  What I saw sort of surprised me, given all of the advice that I see on this web site encouraging people to use countermeasures....GM used to deny that he ever performed any such "encouragment"...but I think those denials have long since proven themselves false...Anyway, in the interest of fairness...because GM and company so frequently cite the NAS study and how damning it is to polygraph....one should look at page 139 and read the section on Countermeasures....in particular, those who are considering taking George's advice on using countermeasures (remember...he doesn't say it directly...he just "encourages you to read Chapter 4 which ironically is dedicated to the topic of countermeasures)....(now, please George, do not get upset with me...I am just ensuring that ALL of the information is out there so peope can make their own INFORMED decisions on what to do....or NOT do).  Forgive me for being a bit scattered...but back to the original topic.  On the referenced pages (139-140), no less than the writers of the NAS Report state that the use of countermeasures is "not risk free for innocent examinees" Also, they cite (and obviously concur) that there IS "evidence that some countermeasures used by innocent examinees can infact increase their chances of appearing deceptive". So it is not a quantum leap to think that the advice that GM and some of his underlings pander to the faithful sheep who come to his altar seeking advice....just may NOT be getting what they want and just MIGHT be getting lead down the proverbial path to ruination....just some food for thought...and leading me back to my oft pronounced solution to all of this "beat the polygraph" drivel....make a conscious decision to either take the test or not....make a conscious decision to tell the truth or not....they go hand in hand....it is NOT rocket science.  Shall you listen to someone who failed their examination and now views himself as the savior of all those confronting their own behaviors...or pursue the position you want and tell the truth...you might be surprised when you tell the truth, how it works to your benefit.....just food for thought....