Child pornography lover passes his own polygraph.

[notguilty1]

Does a civil court need "proof" before finding a judgement?  No, only a preponderance of the presented evidence!

What does a criminal court need? Only a preponderance of the presented evidence? Or does it require more?

Criminal cases require proof beyond a reasonable doubt.

[Sergeant1107]

ng1

When an examiner makes the claim that polygraph accuracy is 99% he as mistaken as you are to claim 50 50 or coin toss accuracy.  They overstate you understate.  Have you, yourself, reviewed the latest research in order to form your own opinion?  Or like Mr Cullen do you have to ask someone else where to find the information?

My own experiences were sufficient to convince me that the polygraph is not accurate.  I told the truth on four polygraph exams and only passed once.

Between the examiner and the examinee, there is only one person in each test who knows whether the polygraph results are accurate.  The examiner can make an educated guess based on their training and experience, the examinee knows for certain.

[Sergeant1107]

What about when someone is accused of a crime and 1 1/2 years later he hires a polygrapher, and he "passes"?

Should he be set free, OR would you be skeptical of him.  Do you think he could read your website in advance and pass a test?

Child porn on his computer agent downloaded from it via limewire and when his house raided, low and behold he had all these pictures of a 7 yo girl on his computer and videos with kids having sex with adults.  in unallocated space he had adult and child erotica and erotic stories of daddys with daughters.Trying to say he just put those used harddrives on his computer.

Now I realize this is the reverse of what most of your posters discuss.

Polygraphers chime in too!!!!

It is most logical to believe evidence over a polygraph.  If polygraphs were accurate enough to rise to the level of "evidence" they would be used as such.

Even Sackett has claimed that police don't resort to polygraphs until all other leads have been exhausted.  Do you think they would wait for such a desperate circumstance if the polygraph results were accurate and held actual evidentiary value?

[11bimmergirl]

ng1

When an examiner makes the claim that polygraph accuracy is 99% he as mistaken as you are to claim 50 50 or coin toss accuracy.  They overstate you understate.  Have you, yourself, reviewed the latest research in order to form your own opinion?  Or like Mr Cullen do you have to ask someone else where to find the information?

Ok, what is the latest research, so we can get back on track!!! :-/ :-/

[pailryder]

11bimmergirl

You need to request a quality control review by a second uninvolved examiner to answer your question about this particular test.  Every professional private examiner expects no less.  If he or his examiner balks at your request and will not provide the charts for review, you have your answer.  A discussion of overall rates will not provide much guidence.  

[T.M. Cullen]

Ok, what is the latest research, so we can get back on track!!! Undecided Undecided

http://www.nap.edu/openbook.php?record_id=10420&page=213

Here is an excerpt:"Overestimation For the reasons cited, we believe that estimates of polygraph accuracy from existing research overestimate accuracy in actual practice, even for specific-incident investigations. The evidence is insufficient to allow a quantitative estimate of the size of the overestimate.

Estimate of Accuracy Notwithstanding the limitations of the quality of the empirical research and the limited ability to generalize to real-world settings, we conclude that in populations of examinees such as those represented in the polygraph research literature, untrained in countermeasures, specific-incident polygraph tests for event-specific investigations can discriminate lying from truth telling at rates well above chance, though well below perfection.

Accuracy may be highly variable across situations. The evidence does not allow any precise quantitative estimate of polygraph accuracy or provide confidence that accuracy is stable across personality types, sociodemographic groups, psychological and medical conditions, examiner and examinee expectancies, or ways of administering the test and selecting questions. In particular, the evidence does not provide confidence that polygraph accuracy is robust against potential countermeasures. There is essentially no evidence on the incremental validity of polygraph testing, that is, its ability to add predictive value to that which can be achieved by other methods."

Note:  My underlining above.  The above is talking about use of polygraph when an actual crime has been committed or a specific incident has occurred and is being tested for.  Rates of accuracy for employment screening is way less.  

Read also  http://antipolygraph.org/articles/article-051.pdf

which discusses:

1)  Probability that a person who PASSES the test is actually telling the truth (NPV).

2)  Probability that a person who FAILS the test is actually being DECEPTIVE (PPV).

Above report studied preemployment screening tests only, I believe.




TC

[Hunter]

That is review of selected research, not research.  Please post the actual research referred to in the report.  

[Sergeant1107]

That is review of selected research, not research.  Please post the actual research referred to in the report.  

Selected research is still research.  There were no claims made that the NAS research study used every scrap of availabe research ever done on the polygraph.

The reference material used in the NAS research study are listed here: http://www.nap.edu/openbook.php?record_id=10420&page=232.

[polytechnic]

FYI, I do not "sit in judgement", I evaluate all available information, including the results of a polygraph test to identitfy those less than 100%  forthcoming.  George makes a good point.  A polygraph examiner should never enter the test assuming anything, I certainly try not to.

Sackett      

Sackett,

Why is it that many examiners prefer to peruse the examinees file or personal dossier prior to testing? Doesn't that behaviour sort of place in doubt your claim to be the only (or one of the few) unbiased, impartial examiners.

Do you always trust the polygraph 'result' without a shadow of doubt ?
Have you ever suspected that you may have called a FP ?

If the examinee is hypertensive and unknowingly displays apnoea type breathing, would you automatically suspect CM behaviour ? How would you address that situation ?

Regards,

[sackett]

FYI, I do not "sit in judgement", I evaluate all available information, including the results of a polygraph test to identitfy those less than 100%  forthcoming.  George makes a good point.  A polygraph examiner should never enter the test assuming anything, I certainly try not to.

Sackett      

Sackett,

Why is it that many examiners prefer to peruse the examinees file or personal dossier prior to testing? Doesn't that behaviour sort of place in doubt your claim to be the only (or one of the few) unbiased, impartial examiners.

Do you always trust the polygraph 'result' without a shadow of doubt ?
Have you ever suspected that you may have called a FP ?

If the examinee is hypertensive and unknowingly displays apnoea type breathing, would you automatically suspect CM behaviour ? How would you address that situation ?

Regards,

I think it is appropriate to review the case facts so we can know what we are talking about.  Nothing sillier than an examiner trying to talk intelligently about something they know nothing of.  And, no.  I do not think it unduly prejudices an examiner.  I have tested many people where the facts were against them and they passed, and visa-versa.

I have certainly had tests where I questioned the results.  Any examiner should be able to admit it.  Remember, we're dealing with human beings, therefore, as I have stated previously, things can be "screwy" for a lot of reasons (Please don't ask me to list them, I'm tired).  If I find a mistake in my testing procedure or (or sometimes) the examinee's actions, I almost always offer a re-examination.  I stay focused on trying to obtain the truth, not a specific result.

As for false positives.  I have probably had some (statistics would be so polite to me).  However, I can not recall an examination where I called the examinee deceptive and later, evidence exonerated them.

As for hypertension, etc, I do not automatically see apnea as CM's.  If it is the normal state of the individual, then it should be taken into consideration.  What is there to "address" if it is normal?

Sackett

[Hunter]

Sergeant,

In 1990, Norman Ansley1 published a report of polygraph validity from studies of real cases conducted since 1980. Researchers conducted twelve validity studies based on 3,174 real cases. Polygraphist's decisions in those cases were compared to other results such as confessions, factual evidence and judicial dispositions. The results, assuming every disagreement was a polygraph error, indicated a validity of 98% when polygraphists score their own polygraph charts. According to Matte2, the algorithms that score computerized polygraph tests are correct about 95% of the time.
References:
1. Ansley, Norman, (ed.) (1997). November-December, "The Validity and Reliability of Polygraph Testing," American Polygraph Association Newsletter, 30 (6): 6


This is research, not a report of studies of research.  It does report the accuracy of polygraph in one research project by Dr. Norman Ansley.  Where is your research from any one source that actually conducted the research?

[George W. Maschke]

Sergeant,

In 1990, Norman Ansley1 published a report of polygraph validity from studies of real cases conducted since 1980. Researchers conducted twelve validity studies based on 3,174 real cases. Polygraphist's decisions in those cases were compared to other results such as confessions, factual evidence and judicial dispositions. The results, assuming every disagreement was a polygraph error, indicated a validity of 98% when polygraphists score their own polygraph charts. According to Matte2, the algorithms that score computerized polygraph tests are correct about 95% of the time.
References:
1. Ansley, Norman, (ed.) (1997). November-December, "The Validity and Reliability of Polygraph Testing," American Polygraph Association Newsletter, 30 (6): 6


This is research, not a report of studies of research.  It does report the accuracy of polygraph in one research project by Dr. Norman Ansley.  Where is your research from any one source that actually conducted the research?

As discussed previously on this forum by myself and Dr. Richardson, the "study" to which you refer ("The Validity and Reliability of Polygraph Testing") is a non-peer-reviewed meta-study of mostly non-peer-reviewed studies that was prepared for an interested party (the American Polygraph Association) by a past president of that association (Norm Ansley). It does not merit serious consideration by anyone seeking a science-based assessment of polygraph accuracy.

[Hunter]

AnalSphincter

Ex Member




 Re: Some Actually Credible Research
Reply #22 - Feb 25th, 2005, 1:36pm    Drew Richardson wrote on Feb 25th, 2005, 12:58pm:
A.S.,

Apparently you have missed this one in your various responses.  George Maschke writes:


I have known, spoken to, and worked with Norm Ansley in the late 1980's and early 1990's.  I found him to be both pleasant to work with and an honorable gentleman.  That having been said, George is precisely correct.  Norm was a well-known polygraph advocate and hardly a suitable candidate for putting together what would be considered an unbiased, neutral and meaningful  compendium.  George's characterization of that compendium is also right on target.  It is no surprise that the National Academy of Sciences in its various deliberations and recent report on polygraphy has called for the separation of the funding, conduct, and publication of polygraph research from individuals and the community which profits from the ongoing practice of polygraphy and handled by various serious research centers, i.e., the DOE National Laboratories, NIH, etc.  Until such is done, there will be very little credibility associated with said research.


Hello again, Drew.  No, I didn't miss anything.  I just didn't consider that post important enough to counter.  Since you point it out, though, I will say this:

Those studies are as "credible" as anything the "anti" people have available on this site.  You are right, though, about the need for additional research.  Right now, there is an "anti" side with its less than totally credible studies and a "pro" side with its own less than totally credible studies.  At least the "pro" side has experience in using the instrument in question to add a bit more credibility to its argument.

As Gino should know by now, and as you and George should have realized yourselves, for every questionable study you can come up with and claim to be valid, the "pro" people can counter with one of their own.  It's like "proving" that God exists: I can point to a myriad of things in Nature that "prove" there is order which must come from God, while you could point out a myriad of things in Nature that "prove" there is disorder and therefore no God.  Neither side proves anything.

This website proves only its agenda, which is to discredit a process through easily refutable information.

This post is from the one you hyperlinked George.  It says accurately what I believe to be true about your quotes on research.  You have no research that is peer reviewed to discredit polygraph, only quips and quotes from your own slanted view of polygraph.  When actual research is submitted you dismiss it as "Non Schientific", so where is your peer reviewed reseearch?  I have not seen it, please present it.

[George W. Maschke]

Hunter,

There simply is no body of peer-reviewed research proving that polygraphic lie tests reliably work at better-than-chance levels under field conditions. I'm not claiming that polygraphy has been proven not to work, but rather that -- in the 90 or so years since William Moulton Marston unveiled the lie detector -- it has not been proven to work.

[Hunter]

Then your statement is "I have no peer reviewed research".  Your use of the polygraph industries research is research and you may wish to attack all of the research that supports polygraph, however you have no research showing it is a coin toss.  You have suppositions and innuendo that supports your position, no research.  This is a circular argument that only circles, and proves nothing.